Added link to SDK API documentation.

Updated product description.

Changes in this update
 - Removed code from AIP which propagates ExpectSpeech initiator strings to subsequent Recognize events. This code will be re-introduced when AVS starts sending initiator strings.

    Changes in this update
    - Implemented `setOffSet` in `MediaPlayer`.
    - Updated `LoggerUtils.cpp` to address
      (alexa#77).

    - Bug fix to address incorrect stop behavior caused when Audio Focus
      is set to `NONE` and released. This addresses
      (alexa#129).
    - Bug fix for intermittent failure in `handleMultipleConsecutiveSpeaks`.
    - Bug fix for `jsonArrayExist` incorrectly parsing JSON when trying
      to locate array children.
    - Bug fix for ADSL test failures with `sendDirectiveWithoutADialogRequestId`.
    - Bug fix for `SpeechSynthesizer` showing the wrong UX state when a
      burst of `Speak` directives are received.
    - Bug fix for recursive loop in `AudioPlayer.Stop`.

- Changes in this update:

	- Better GStreamer error reporting. MediaPlayer used to only report   `MEDIA_ERROR_UNKNOWN`, now reports more specific errors as defined in `ErrorType.h`.
	- Codebase has been formatted for easier reading.
	- `DirectiveRouter::removeDirectiveHandler()` signature changed and now returns a bool indicating if given handler should be successfully removed or not.
	- Cleanup of raw and shared pointers in the creation of `Transport` objects.
	- `HTTP2Stream`s now have IDs assigned as they are acquired as opposed to created, making associated logs easier to interpret.
	- `AlertsCapabilityAgent` has been refactored.
		- Alert management has been factored out into an `AlertScheduler` class.
	- Creation of Reminder (implements Alert) class.
	- Added new capability agent for `PlaybackController` with unit tests.
	- Added Settings interface with unit tests.
	- Return type of `getOffsetInMilliseconds()` changed from `int64_t` to `std::chronology::milliseconds`.
	- Added `AudioPlayer` unit tests.
	- Added teardown for all Integration tests except Alerts.
	- Implemented PlaylistParser.

- Bug fixes:

	- AIP getting stuck in `LISTENING` or `THINKING` and refusing user input on network outage.
	- SampleApp crashing if running for 5 minutes after network disconnect.
	- Issue where on repeated user barge-ins, `AudioPlayer` would not pause. Specifically, the third attempt to “Play iHeartRadio” would not result in currently-playing music pausing.
	- Utterances being ignored after particularly long TTS.
	- GStreamer errors cropping up on SampleApp exit as a result of accessing the pipeline before it’s been setup.
	- Crashing when playing one URL after another.
	- Buffer overrun in Alerts Renderer.
	- [SampleApp crashing when issuing "Alexa skip" command with iHeartRadio.](alexa#153)
	- [`HTTP2Transport` network thread triggering a join on itself.](alexa#127)
	- [`HTTP2Stream` request handling truncating exception messages.](alexa#67)
	- [`AudioPlayer` was attempting an incorrect state transition from `STOPPED` to `PLAYING` through a `playbackResumed`.](alexa#138)

… bugs and seeking help from the AVS developer community.

Changes in this update
* **Enhancements**
  * Updated MediaPlayer to solve stability issues
  * All capability agents were refined to work with the updated MediaPlayer
  * Added the TemplateRuntime capability agent
  * Added the SpeakerManager capability agent
  * Added a configuration option ("sampleApp":"endpoint") that allows the endpoint that SampleApp connects to to be specified without changing code or rebuilding
  * Added very verbose capture of libcurl debug information
  * Added an observer interface to observer audio state changes from AudioPlayer
  * Added support for StreamMetadataExtracted Event. Stream tags found in the stream are represented in JSON and sent to AVS
  * Added to the SampleApp a simple GuiRenderer as an observer to the TemplateRuntime Capability Agent
  * Moved shared libcurl functionality to AVSCommon/Utils
  * Added a CMake option to exclude tests from the "make all" build. Use "cmake <absolute-path-to-source>
  -DACSDK_EXCLUDE_TEST_FROM_ALL=ON" to enable it. When this option is enabled "make unit" and "make integration" still could be used to build and run the tests

* **Bug fixes**:
  * Previously scheduled alerts now play following a restart
  * General stability fixes
  * Bug fix for CertifiedSender blocking forever if the network goes down while it's trying to send a message to AVS
  * Fixes for known issue of Alerts integration tests fail: AlertsTest.UserLongUnrelatedBargeInOnActiveTimer and AlertsTest.handleOneTimerWithVocalStop
  * Attempting to end a tap-to-talk interaction with the tap-to-talk button wouldn't work
  * SharedDataStream could encounter a race condition due to a combination of a blocking Reader and a Writer closing before writing any data
  * Bug-fix for the ordering of notifications within alerts scheduling. This fixes the issue where a local-stop on an alert would also stop a subsequent alert if it were to begin without delay

* **Known Issues**

* Capability agent for Notifications is not included in this release
* Inconsistent playback behavior when resuming content ("Alexa, pause." / "Alexa, resume."). Specifically, handling playback offsets, which causes the content to play from the start. This behavior is also occasionally seen with "Next" /
"Previous".
* `ACL`'s asynchronous receipt of audio attachments may manage resources poorly in scenarios where attachments are received but not consumed.

Changes in this update
* **Enhancements**..
  * Added comments to `AlexaClientSDKConfig.json`. These descriptions provide additional guidance for what is expected for each field...
  * Enabled pause and resume controls for Pandora...

* **Bug Fixes**..
  * Bug fix for [issue alexa#329](alexa#329) - `HTTP2Transport` instances no longer leak when `SERVER_SIDE
  * Bug fix for [issue alexa#189](alexa#189) - Fixed a race condition in the `Timer` class that sometimes
  * Bug fix for a race condition that caused `SpeechSynthesizer` to ignore subsequent `Speak` directives...
  * Bug fix for corrupted mime attachments.

**Enhancements**
* ContextManager now passes the namespace/name of the desired state to StateProv
iderInterface::provideState().  This is helpful when a single StateProvider obje
ct provides multiple states, and needs to know which one ContextManager is askin
g for.
* The mime parser was hardened against duplicate boundaries.
* Added functionality to add and remove AudioPlayer observers to the DefaultClie
nt.
* Unit tests for Alerts were added.
* Added en-IN, en-CA and ja-JP to the SampleApp locale selection menu.
* Added default alert and timer audio data to the SDK SampleApp.  There is no lo
nger a requirement to download these audio files and configure them in the json
configuration file.
* Added support in SDS Reader and AttachmentReader for seeking into the future.
 This allows a reader to move to an index which has not yet arrived in the SDS a
nd poll/block until it arrives.
* Added support for blocking Writers in the SharedDataStream class.
* Changed the default status code sent by MessageRequestObserverInterface::onSen
dCompleted() to SERVER_OTHER_ERROR, and mapped HTTP code 500 to SERVER_INTERNAL_
ERROR_V2.
* Added support for parsing stream duration out of playlists.
* Added a configuration option ("sampleApp":"displayCardsSupported") that allows
 the displaying of display cards to be enabled or disabled.
* Named Timers and Reminders have been updated to fall back to the on-device bac
kground audio sound when cloud urls cannot be accessed or rendered.

**Bug Fixes**
* Removed floating point dependencies from core SDK libraries.
* Fixed bug in SpeechSynthesizer where it's erroneously calling stop more than once.
* Fixed an issue in ContentFetcher where it could hang during destruction until an active GET request completed.
* Fixed a couple of parsing bugs in LibCurlHttpContentFetcher related to case-sensitivity and mime-type handling.
* Fixed a bug where MediaPlayerObserverInterface::onPlaybackResumed() wasn't being called after resuming from a pause with a pending play/resume.
* Fixed a bug in LibCurlContentFetcher where it could error out if data is written to the SDS faster than it is consumed.
* The GStreamer-based MediaPlayer reference implementation now uses the ACL HTTP configured client.
  * An API change has been made to MediaPlayerInterface::setSource(). This method now takes in an optional offset as well to allow for immediately streaming to the offset if possible.
  * Next and Previous buttons now work with Audible.
  * Pandora resume stuttering is addressed.
  * Pausing and resuming Amazon music no longer seeks back to the beginning of the song.
* libcurl CURLOPT_NOSIGNAL option is set to 1 (https://curl.haxx.se/libcurl/c/CURLOPT_NOSIGNAL.html) to avoid crashes  observed in SampleApp.
* Fixed the timing of the PlaybackReportIntervalEvent and PlaybackReportDelayEvent as specified in the directives.
* Fixed potential deadlocks in MediaPlayer during shutdown related to queued callbacks.
* Fixed a crash in MediaPlayer that could occur if the network is disconnected during playback.
* Fixed a bug where music could keep playing while Alexa is speaking.
* Fixed a bug which was causing problems with pause/resume and next/previous with Amazon Music.
* Fixed a bug where music could briefly start playing between speaks.
* Fixed a bug where HLS playlists would stop streaming after the initial playlist had been played to completion.
* Fixed a bug where Audible playback could not advance to the next chapter.
* Fixed some occurrences of SDK entering the IDLE state during the transition between Listening and Speaking states.
* Fixed a bug where PlaybackFinished events were not reporting the correct offset.
  * An API change has been made to MediaPlayerInterface::getOffset().  This method is now required to return the final offset when called after playback has stopped.
* Fixed a problem where AIP was erroneously resetting its state upon getting a cancelDirective() callback.

**Known Issues**
* Capability agent for Notifications is not included in this release.
* `ACL`'s asynchronous receipt of audio attachments may manage resources poorly in scenarios where attachments are received but not consumed.
* GUI cards don't show for Kindle.
* The new SpeechSynthesizerState state values GAINING_FOCUS and LOSING_FOCUS were added as part of a work-around.  The will likely be removed in subsequent releases.
* With the gstreamer-based MediaPlayer, after muting and unmuting, the next item starts playing rather than continuing with the current item.

…. To ask a question or report an issue, please review our Contribution Guide https://github.com/alexa/avs-device-sdk/blob/master/CONTRIBUTING.md.

Changes in this update:

**Enhancements**
* Added the Notifications Capability Agent. This allows a client to receive notification indicators from Alexa.
* Added support for the `SoftwareInfo` event. This code is triggered in the `SampleApp` by providing a positive decimal integer as the "firmwareVersion" value in "sampleApp" object of the `AlexaClientSDKConfig.json`. The reported firmware version can be updated after starting the `SampleApp` by calling `SoftwareInfoSender::setFirmwareVersion()`. This code path can be exercised in the `SampleApp` with the new command: `f`.
* Added unit tests for Alerts.
* The GStreamer-based pipeline allows for the configuration of `MediaPlayer` output based on information provided in `Config`.
* Playlist streaming now uses a `BLOCKING` writer, which improves streaming efficiency.

**Bug Fixes**
* Fixed bug where `SpeechSynthesizer` would not stop playback when a state change timeout was encountered.
* Fixed the `SampleApplication` destructor to avoid segfaults if the object is not constructed correctly.
* Fixed bug where `AudioPlayer` would erroneously call `executeStop()` in `cancelDirective()`.
* [Issue 396](alexa#396) - Fixed bug for compilation error with GCC7 in `AVSCommon/SDKInterfaces/include/AVSCommon/SDKInterfaces/Audio/AlertsAudioFactoryInterface.h`
* [Issue 384](alexa#384) - Fixed bug that caused `AuthServer.py` to crash.
* Fixed bug where a long delay was encountered after pausing and resuming a large Audible chapter.
* Fixed bug that caused named timers and reminders to loop for an additional `loopCount` .
* Fixed memory corruption bug in `MessageInterpreter`.
* Fixed illegal memory accesses in `MediaPlayer` logging.

**Known Issues**
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* Display Cards for Kindle don't render.
* If using the GStreamer-based `MediaPlayer` implementation, after muting and un-muting an audio item, the next item in the queue will begin playing rather than continuing playback of the originally muted audio item.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* Music playback doesn't immediately stop when a user barges-in on iHeartRadio.

Updated third-party dev kit list + links to getting started guide.

Changes in this update:

**Enhancements**
* Added the `ExternalMediaPlayer` Capability Agent. This allows playback from music providers that control their own playback queue. Example: Spotify.
* Added support for AU and NZ to the `SampleApp`.
* Firmware version can now be sent to Alexa via the `SoftwareInfo` event. The firmware version is specified in the config file under the `sampleApp` object as an integer value named [`firmwareVersion`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L52).
* The new `f` command was added to the `SampleApp` which allows the firmware version to be updated at run-time.
* Optional configuration changes have been introduced. Now a [default log level](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L93) can be set for `ACSDK_LOG_MODULE` components, globally or individually. This value is specified under a new root level configuration object called `logger`, and the value itself is named `logLevel`. This allows you to limit the degree of logging to that default value, such as `ERROR`or `INFO`.

**Bug Fixes**
* Fixed bug where `AudioPlayer` progress reports were not being sent, or were being sent incorrectly.
* [Issue 408](alexa#408) - Irrelevant code related to `UrlSource` was removed from the `GStreamer-based MediaPlayer` implementation.
* The `TZ` variable no longer needs to be set to `UTC` when building the `SampleApp`.
* Fixed a bug where `CurlEasyHandleWrapper` logged unwanted data on failure conditions.
* Fixed a bug to improve `SIGPIPE` handling.
* Fixed a bug where the filename and classname were mismatched. Changed `UrlToAttachmentConverter.h` to `UrlContentToAttachmentConverter.h`,and `UrlToAttachmentConverter.cpp` to `UrlContentToAttachmentConverter.cpp`

**Known Issues**
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* Display Cards for Kindle don't render.
* If using the GStreamer-based `MediaPlayer` implementation, after muting and un-muting an audio item, the next item in the queue will begin playing rather than continuing playback of the originally muted audio item.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* Music playback doesn't immediately stop when a user barges-in on iHeartRadio.

Changes in this update:

**Enhancements**
* `rapidJson` is now included with "make install".
* Updated the `TemplateRuntimeObserverInterface` to support clearing of `displayCards`.
* Added Windows SDK support, along with an installation script (MinGW-w64).
* Updated `ContextManager` to ignore context reported by a state provider.
* The `SharedDataStream` object is now associated by playlist, rather than by URL.
* Added the `RegistrationManager` component. Now, when a user logs out all persistent user-specific data is cleared from the SDK. The log out functionality can be exercised in the sample app with the new command: `k`.

**Bug Fixes**
* [Issue 400](alexa#400) Fixed a bug where the alert reminder did not iterate as intended after loss of network connection.
* [Issue 477](alexa#477) Fixed a bug in which Alexa's weather response was being truncated.
* Fixed an issue in which there were reports of instability related to the Sensory engine. To correct this, the `portAudio` [`suggestedLatency`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L62) value can now be configured.

**Known Issues**
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* Music playback doesn't immediately stop when a user barges-in on iHeartRadio.
* The Windows sample app sometimes hangs on exit.
* GDP receives a `SIGPIPE` when troubleshooting the Windows sample app.

Changes in this update:

**Enhancements**
* `AuthDelegate` and `AuthServer.py` have been replaced by `CBLAUthDelegate`, which provides a more straightforward path to authorization.
* Added a new configuration property called [`cblAuthDelegate`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L2). This object specifies parameters for `CBLAuthDelegate`.
* Added a new configuration property called [`miscDatabase`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L34), which is a generic key/value database to be used by various components.
* Added a new configuration property called [`dcfDelegate`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L17) This object specifies parameters for `DCFDelegate`. Within this object, values were added for the 'endpoint' and `overridenDcfPublishMessageBody`. 'endpoint' is the endpoint to connect to in order to send device capabilities. `overridenDcfPublishMessageBody`is the message that will get sent out to the Capabilities API. Note: values within the `dcfDelegate` object will only work in `DEBUG` builds.
* Added a new configuration property called [`deviceInfo`](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json#L9) which specifies device-identifying information for use by the Device Capability Framework (DCF), and for authorization (CBLAuthDelegate).
* Updated the Directive Sequencer to support wildcard directive handlers. This allows a handler for a given AVS interface to register at the namespace level, rather than specifying the names of all directives within that namespace.
* Updated the Raspberry Pi installation script to include `alsasink` in the configuration file.
* Added `audioSink` as a configuration option. This allows users to override the audio sink element used in `Gstreamer`.
* Added an interface for monitoring internet connection status: `InternetConnectionMonitorInterface.h`.
* The Alexa Communications Library (ACL) is no longer required to wait until authorization has succeeded before attempting to connect to AVS. Instead, `HTTP2Transport` handles waiting for authorization to complete.
* Added the Device Capabilities Framework (DCF) delegate. Device capabilities can now be sent for each capability interface using DCF publish messages.
* The sample app has been updated to send DCF publish messages, which will automatically occur when the sample app starts. Note: a DCF publish message must be successfully sent in order for communication with AVS to occur.
* The SDK now supports HTTP PUT messages.
* Added support for opt-arg style arguments and multiple configuration files. Now, the sample app can be invoked by either of these commands: `SampleApp <configfile> <debuglevel>` OR `SampleApp -C file1 -C file2 ... -L loglevel`.

**Bug Fixes**
* Issues [447](alexa#447) and [553](alexa#553) Fixed the `AttachmentRenderSource`'s handling of `BLOCKING` `AttachmentReaders`.
* Updated the `Logger` implementation to be more resilient to `nullptr` string inputs.
* Fixed a `TimeUtils` utility-related compile issue.
* Fixed a bug in which alerts failed to activate if the system was restarted without network connection.
* Fixed Android 64-bit build failure issue.

**Known Issues**
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* Some ERROR messages may be printed during start-up event if initialization proceeds normally and successfully.
* If an unrecoverable authorization error or an unrecoverable DCF error is encountered, the sample app may crash on shutdown.
* If a non-CBL `clientId` is included in the `deviceInfo` section of `AlexaClientSDKConfig.json`, the error will be reported as an unrecoverable authorization error, rather than a more specific error.

https://issues.amazon.com/issues/ACSTechDocs-156

https://issues.amazon.com/issues/ACSTechDocs-156

Changes in this update:

Enhancements
* Added the Bluetooth interface, which manages the Bluetooth connection between Alexa-enabled products and peer devices. This release supports A2DP-SINK and AVRCP profiles. Note: Bluetooth is optional and is currently limited to Raspberry Pi and Linux platforms.
* Added new Bluetooth dependencies for Linux and Raspberry Pi.
* Device Capability Framework (DCF) renamed to Capabilities.
* Updated the non-CBL client ID error message to be more specific.
* Updated the sample app to enter a limited interaction mode after an unrecoverable error.

Bug Fixes
* Issue 597 - Fixed a bug where the sample app did not respond to locale change settings.

* Fixed issue where GStreamer 1.14 MediaPlayerTest failed on Windows.
* Fixed an issue where a segmentation fault was triggered after unrecoverable error handling.

Known Issues
* The ACL may encounter issues if audio attachments are received but not consumed.
* SpeechSynthesizerState currently uses GAINING_FOCUS and LOSING_FOCUS as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When streaming silence via Bluetooth, the Alexa companion app will sometimes indicate that media content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* When streaming content via Bluetooth, under certain conditions playback will fail to resume and the sample app hangs on exit. This is due to a conflict between the GStreamer pipeline and the Bluetooth agent.
* On Raspberry Pi, when streaming audio via Bluetooth, sometimes the audio stream stutters.
* On Raspberry Pi, BlueALSA must be terminated each time the device boots. See Raspberry Pi Quick Start Guide for more information.

Changes in this update:

Enhancements

Added local stop functionality. This allows a user to stop an active function, such as an alert or timer, by uttering "Alexa, stop" when an Alexa-enabled product is offline.
Alerts in the background now stream in 10 sec intervals, rather than continuously.
Added support for France to the sample app.
friendlyName can now be updated for BlueZ implementations of BlueZBluetoothDevice and BlueZHostController.
Bug Fixes

Fixed an issue where the Bluetooth agent didn't clear user data upon reset, including paired devices and the uuidMapping table.
Fixed MediaPlayer threading issues. Now each instance has it's own glib main loop thread, rather than utilizing the default main context worker thread.
Fixed segmentation fault issues that occurred when certain static initializers needed to be initialized in a certain order, but the order wasn't defined.
Known Issues

The ACL may encounter issues if audio attachments are received but not consumed.
SpeechSynthesizerState currently uses GAINING_FOCUS and LOSING_FOCUS as a workaround for handling intermediate state. These states may be removed in a future release.
The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
When a source device is streaming silence via Bluetooth, the Alexa companion app indicates that audio content is streaming.
The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
On Raspberry Pi, when streaming audio via Bluetooth, sometimes the audio stream stutters.
On Raspberry Pi, BlueALSA must be terminated each time the device boots. See Raspberry Pi Quick Start Guide for more information.

Changes in this update:

**Enhancements**

* Added support for adjustment of alert volume.
* Added support for deletion of multiple alerts.
* The following `SpeakerInterface::Type` enumeration values have changed:
  * `AVS_SYNCED` is now `AVS_SPEAKER_VOLUME`.
  * `LOCAL` is now `AVS_ALERTS_VOLUME`.

**Known Issues**
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa companion app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* On Raspberry Pi, when streaming audio via Bluetooth, sometimes the
audio stream stutters.

…se Agreement. See NOTICE.txt for additional details.

Changes in this update:

Enhancements

    Added Android SDK support, which includes new implementations of the MediaPlayer, audio recorder, and logger.
    Added the InteractionModel interface, which enables Alexa Routines.
    Optional configuration changes have been introduced. Now a network interface can be specified to connect to the SDK via curl.
    Build options can be configured to support Android.
    Added GUI 1.1 support. The PlaybackController has been extended to support new control functionality, and the System interface has been updated to support SoftwareInfo.

Bug Fixes

    Installation script execution time has been reduced. Now a single branch clone is used, such as the master branch.
    Issue 846 - Fixed a bug where audio stuttered on slow network connections.
    Removed the SpeakerManager constructor check for non-zero speakers.
    Issue 891 - Resolved incorrect offset in the PlaybackFinished event.
    Issue 727 - Fixed an issue where the sample app behaved erratically upon network disconnection/reconnection.
    Issue 910 - Fixed a GCC 8+ compilation issue. Note: issues related to -Wclass-memaccess will still trigger warnings, but won't fail compilation.
    Issue 871 Issue 880 - Fixed compiler warnings.
    Fixed a bug where Ted Talks would not stream via TuneIn.
    Fixed an issue where the PryonLiteKeywordDetector would not restart.
    Fixed an issue where PlaybackStutterStarted and PlaybackStutterFinished events were not being sent due to a missing Gstreamer queue element.
    Fixed a bug where the CapabilitiesDelegate database was not being cleared upon logout.
    Fixed in issue that caused the following compiler warning “class has virtual functions but non-virtual destructor”.
    Fixed a bug where BlueZDeviceManager was not properly destroyed.
    Fixed a bug that occurred when the initializer list was converted to std::unordered_set.
    Fixed a build error that occurred when building with BUILD_TESTING=Off.

Known Issues
* The ACL may encounter issues if audio attachments are received but not consumed.
* SpeechSynthesizerState currently uses GAINING_FOCUS and LOSING_FOCUS as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa companion app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* On Raspberry Pi, when streaming audio via Bluetooth, sometimes the audio stream stutters.
* These CapabilitiesDelegateTest tests have been temporarily disabled to prevent build errors for the Android build: CapabilitiesDelegateTest.withCapabilitiesHappyCase, CapabilitiesDelegateTest.republish, CapabilitiesDelegateTest.testClearData.
* make integration is currently not available for Android. In order to run integration tests on Android, you'll need to manually upload the test binary file along with the any input file. At that point, the adb can be used to run the integration tests.
* On Raspberry Pi running Android Things with HDMI output audio, beginning of speech is truncated when Alexa responds to user TTS.
* Spotify does not completely shut down when the sample app quits.

…v1.9 code base

Changes in this update:

**Enhancements**

* New optional configuration for [EqualizerController](https://github.com/alexa/avs-device-sdk/blob/v1.10.0/Integration/AlexaClientSDKConfig.json#L154). The EqualizerController interface allows you to adjust equalizer settings on your product, such as decibel (dB) levels and modes.
* Added reference implementation of the EqualizerController for GStreamer-based (MacOS, Linux, and Raspberry Pi) and OpenSL ES-based (Android) MediaPlayers. Note: In order to use with Android, it must support OpenSL ES.
* New optional configuration for the [TemplateRuntime display card value](https://github.com/alexa/avs-device-sdk/blob/v1.10.0/Integration/AlexaClientSDKConfig.json#L144).
* A configuration file generator script, `genConfig.sh` is now included with the SDK in the **tools/Install** directory. `genConfig.sh` and it's associated arguments populate `AlexaClientSDKConfig.json` with the data required to authorize with LWA.
* Added Bluetooth A2DP source and AVRCP target support for Linux.
* Added Amazon for Business (A4B) support, which includes support for handling the new [RevokeAuthorization](https://developer.amazon.com/docs/alexa-voice-service/system.html#revokeauth) directive in the Settings interface. A new CMake option has been added to enable A4B within the SDK, `-DA4B`.
* Added locale support for IT and ES.
* The Alexa Communication Library (ACL), `CBLAUthDelegate`, and sample app have been enhanced to detect de-authorization using the new `z` command.
* Added `ExternalMediaPlayerObserver`, which receives notification of player state, track, and username changes.
* `HTTP2ConnectionInterface` was factored out of `HTTP2Transport` to enable unit testing of `HTTP2Transport` and re-use of `HTTP2Connection` logic.

**Bug Fixes**

* Fixed a bug in which `ExternalMediaPlayer` adapter playback wasn't being recognized by AVS.
* [Issue 973](alexa#973) - Fixed issues related to `AudioPlayer` where progress reports were being sent out of order or with incorrect offsets.
* An `EXPECTING`, state has been added to `DialogUXState` in order to handle `EXPECT_SPEECH` state for hold-to-talk devices.
* [Issue 948](alexa#948) - Fixed a bug in which the sample app was stuck in a listening state.
* Fixed a bug where there was a delay between receiving a `DeleteAlert` directive, and deleting the alert.
* [Issue 839](alexa#839) - Fixed an issue where speech was being truncated due to the `DialogUXStateAggregator` transitioning between a `THINKING` and `IDLE` state.
* Fixed a bug in which the `AudioPlayer` attempted to play when it wasn't in the `FOREGROUND` focus.
* `CapabilitiesDelegateTest` now works on Android.
* [Issue 950](alexa#950) - Improved Android Media Player audio quality.
* [Issue 908](alexa#908) - Fixed compile error on g++ 7.x in which includes were missing.

Changes in this update:

**Enhancements**

* Added support for the new Alexa [DoNotDisturb](https://developer.amazon.com/docs/alexa-voice-service/donotdisturb.html) interface, which enables users to toggle the do not disturb (DND) function on their Alexa built-in products.
* The SDK now supports [Opus](https://opus-codec.org/license/) encoding, which is optional. To enable Opus, you must [set the CMake flag to `-DOPUS=ON`](https://github.com/alexa/avs-device-sdk/wiki/Build-Options#Opus-encoding), and include the [libopus library](https://github.com/alexa/avs-device-sdk/wiki/Dependencies#core-dependencies) dependency in your build.
* The MediaPlayer reference implementation has been expanded to support the SAMPLE-AES and AES-128 encryption methods for HLS streaming.
  * AES-128 encryption is dependent on libcrypto, which is part of the required openSSL library, and is enabled by default.
  * To enable [SAMPLE-AES](https://github.com/alexa/avs-device-sdk/wiki/Dependencies#core-dependencies/Enable-SAMPLE-AES-decryption) encryption, you must set the `-DSAMPLE_AES=ON` in your CMake command, and include the [FFMPEG](https://github.com/alexa/avs-device-sdk/wiki/Dependencies#core-dependencies/Enable-SAMPLE-AES-decryption) library dependency in your build.
* A new configuration for [deviceSettings](https://github.com/alexa/avs-device-sdk/blob/v1.11.0/Integration/AlexaClientSDKConfig.json#L59) has been added.This configuration allows you to specify the location of the device settings database.
* Added locale support for es-MX.

**Bug Fixes**

* Fixed an issue where music wouldn't resume playback in the Android app.
* Now all equalizer capabilities are fully disabled when equalizer is turned off in configuration file. Previously, devices were unconditionally required to provide support for equalizer in order to run the SDK.
* [Issue 1106](alexa#1106) - Fixed an issue in which the `CBLAuthDelegate` wasn't using the correct timeout during request refresh.
* [Issue 1128](alexa#1128) - Fixed an issue in which the `AudioPlayer` instance persisted at shutdown, due to a shared dependency with the `ProgressTimer`.
* Fixed in issue that occurred when a connection to streaming content was interrupted, the SDK did not attempt to resume the connection, and appeared to assume that the content had been fully downloaded. This triggered the next track to be played, assuming it was a playlist.
* [Issue 1040](alexa#1040) - Fixed an issue where alarms would continue to play after user barge-in.

**Known Issues**

* `PlaylistParser` and `IterativePlaylistParser` generate two HTTP requests (one to fetch the content type, and one to fetch the audio data) for each audio stream played.
* Music playback history isn't being displayed in the Alexa app for certain account and device types.
* On GCC 8+, issues related to `-Wclass-memaccess` will trigger warnings. However, this won't cause the build to fail, and these warnings can be ignored.
* In order to use Bluetooth source and sink PulseAudio, you must manually load and unload PulseAudio modules after the SDK starts.
* The `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* `make integration` is currently not available for Android. In order to run integration tests on Android, you'll need to manually upload the test binary file along with any input file. At that point, the adb can be used to run the integration tests.
* On Raspberry Pi running Android Things with HDMI output audio, beginning of speech is truncated when Alexa responds to user TTS.
* When the sample app is restarted and network connection is lost, alerts don't play.
* When network connection is lost, lost connection status is not returned via local Text-to Speech (TTS).

Changes in this update:

**Enhancements**

* Support was added for the `fr_CA` locale.
* The Executor has been optimized to run a single thread when there are active job in the queue, and to remain idle when there are not active jobs.
* An additional parameter of `alertType` has been added to the Alerts capability agent. This will allow observers of alerts to know the type of alert being delivered.
* Support for programmatic unload and load of PulseAudio Bluetooth modules was added. To enable this feature, there is a [new CMake option](https://github.com/alexa/avs-device-sdk/wiki/CMake-parameters#bluetooth): `BLUETOOTH_BLUEZ_PULSEAUDIO_OVERRIDE_ENDPOINTS`. Note that [libpulse-dev is a required dependency](https://github.com/alexa/avs-device-sdk/wiki/Dependencies#bluetooth) of this feature.
* An observer interface was added for when an active Bluetooth device connects and disconnects.
* The `BluetoothDeviceManagerInterface` instantiation was moved from `DefaultClient` to `SampleApp` to allow applications to override it.
* The `MediaPlayerInterface` now supports repeating playback of URL sources.
* The Kitt.AI wake word engine (WWE) is now compatible with GCC5+.
* Stop of ongoing alerts, management of MessageObservers, and management of CallStateObservers have been exposed through DefaultClient.

**Bug Fixes**

* [Issue 953](alexa#953) - The `MediaPlayerInterface` requirement that callbacks not be made upon a callers thread has been removed.
* [Issue 1136](alexa#1136) - Added a missing default virtual destructor.
* [Issue 1140](alexa#1140) - Fixed an issue where DND states were not synchronized to the AVS cloud after device reset.
* [Issue 1143](alexa#1143) - Fixed an issue in which the SpeechSynthesizer couldn't enter a sleeping state.
* [Issue 1183](alexa#1183) - Fixed an issue where alarm is not sounding for certain timezones
* Changing an alert's volume from the Alexa app now works when an alert is playing.
* Added missing shutdown handling for ContentDecrypter to prevent the `Stop` command from triggering a crash when SAMPLE-AES encrypted content was streaming.
* Fixed a bug where if the Notifications database is empty, due to a crash or corruption, the SDK initialization process enters an infinite loop when it retries to get context from the Notifications capability agent.
* Fixed a race condition that caused `AlertsRenderer` observers to miss notification that an alert has been completed.

**Known Issues**

* `PlaylistParser` and `IterativePlaylistParser` generate two HTTP requests (one to fetch the content type, and one to fetch the audio data) for each audio stream played.
* Music playback history isn't being displayed in the Alexa app for certain account and device types.
* On GCC 8+, issues related to `-Wclass-memaccess` will trigger warnings. However, this won't cause the build to fail and these warnings can be ignored.
* Android error ("libDefaultClient.so" not found) can be resolved by upgrading to ADB version 1.0.40
* When network connection is lost, lost connection status is not returned via local TTS.
* `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* `make integration` is currently not available for Android. In order to run integration tests on Android, you'll need to manually upload the test binary file along with any input file. At that point, the adb can be used to run the integration tests.
* On Raspberry Pi running Android Things with HDMI output audio, beginning of speech is truncated when Alexa responds to user text-to-speech (TTS).
* When the sample app is restarted and network connection is lost, Reminder TTS does not play. Instead, the default alarm tone will play twice.

Changes in this update:

**Bug Fixes**

* Fixed a bug where the same URL was being requested twice when streaming iHeartRadio. Now, a single request is sent.
* Corrected pause/resume handling in `ProgressTimer` so that extra `ProgressReportDelayElapsed` events are not sent to AVS.

**Known Issues**

* Music playback history isn't being displayed in the Alexa app for certain account and device types.
* On GCC 8+, issues related to `-Wclass-memaccess` will trigger warnings. However, this won't cause the build to fail and these warnings can be ignored.
* Android error ("libDefaultClient.so" not found) can be resolved by upgrading to ADB version 1.0.40
* When network connection is lost, lost connection status is not returned via local TTS.
* `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* `make integration` is currently not available for Android. In order to run integration tests on Android, you'll need to manually upload the test binary file along with any input file. At that point, the adb can be used to run the integration tests.
* On Raspberry Pi running Android Things with HDMI output audio, beginning of speech is truncated when Alexa responds to user text-to-speech (TTS).
* When the sample app is restarted and the network connection is lost, the Reminder TTS message does not play. Instead, the default alarm tone will play twice.

Changes in this update:

Release Version 1.13 of Alexa C++ SDK

Changes in this update:
Minor updates to README.md and CHANGELOG.md

Changes in this update:

**Enhancements**

* AudioPlayer can now pre-buffer audio tracks in the Pre-Handle stage.

**Bug Fixes**

* Fixed an issue in the SQLite wrapper code where a `SQLiteStatement` caused a memory corruption issue.
* Fixed a race condition in SpeechSynthesizer that caused crashes.
* Fixed a `cmake` issue that specifies a dependency for Bluetooth incorrectly.
* Fixed a bug that caused Bluetooth playback to start automatically.
* Changed `supportedOperations` from a vector to a set in `ExternalMediaAdapterInterface`.
* Corrected an issue where a `VolumeChanged` event had previously been sent when the volume was unchanged after `setVolume` or `adjustVolume` had been called locally.
* Fixed issue with `IterativePlaylistParser` that prevented live stations on TuneIn from playing on Android.
* Corrected the spelling of "UNINITIALIZED".

**Known Issues**

* Music playback history isn't being displayed in the Alexa app for certain account and device types.
* On GCC 8+, issues related to `-Wclass-memaccess` will trigger warnings. However, this won't cause the build to fail and these warnings can be ignored.
* Android error ("libDefaultClient.so" not found) can be resolved by upgrading to ADB version 1.0.40
* When network connection is lost, lost connection status is not returned via local TTS.
* `ACL` may encounter issues if audio attachments are received but not consumed.
* `SpeechSynthesizerState` currently uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate state. These states may be removed in a future release.
* The Alexa app doesn't always indicate when a device is successfully connected via Bluetooth.
* Connecting a product to streaming media via Bluetooth will sometimes stop media playback within the source application. Resuming playback through the source application or toggling next/previous will correct playback.
* When a source device is streaming silence via Bluetooth, the Alexa app indicates that audio content is streaming.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation is not yet supported.
* On some products, interrupted Bluetooth playback may not resume if other content is locally streamed.
* `make integration` is currently not available for Android. In order to run integration tests on Android, you'll need to manually upload the test binary file along with any input file. At that point, the adb can be used to run the integration tests.
* On Raspberry Pi running Android Things with HDMI output audio, beginning of speech is truncated when Alexa responds to user text-to-speech (TTS).
* When the sample app is restarted and the network connection is lost, the Reminder TTS message does not play. Instead, the default alarm tone will play twice.
* `ServerDisconnectIntegratonTest` tests have been disabled until they can be updated to reflect new service behavior.
* Devices connected before the Bluetooth CA is initialized are ignored.
* The `DirectiveSequencerTest.test_handleBlockingThenImmediatelyThenNonBockingOnSameDialogId` test fails intermittently.

Changes in this update:

**Enhancements**

* Added `SystemSoundPlayer` to [ApplicationUtilities](https://alexa.github.io/avs-device-sdk/namespacealexa_client_s_d_k_1_1application_utilities.html). `SystemSoundPlayer` is a new class that plays pre-defined sounds. Sounds currently supported include the wake word notification and the end of speech tone. This change is internal and you don't need to update your code.
* Removed [Echo Spatial Perception (ESP)](https://developer.amazon.com/blogs/alexa/post/042be85c-5a62-4c55-a18d-d7a82cf394df/esp-moves-to-the-cloud-for-alexa-enabled-devices) functionality from the Alexa Voice Service (AVS) device SDK. Make sure you download and test your devices using the new AVS SDK sample app. If you're using an older version of the sample app, manually remove any references to ESP or errors occur during compile.
* Added `onNotificationReceived` to `NotificationsObserverInterface`. `onNotificationReceived` broadcasts when `NotificationsObserverInterface` receives a new notification, instead of only sending the indicator state. This is important if you support a feature that requires a distinct signal for each notification received. See [NotificationsObserverInterface](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1sdk_interfaces_1_1_notifications_observer_interface.html) for more details.
* Added support for [Multilingual Mode](https://developer.amazon.com/docs/alexa-voice-service/system.html#localecombinations). With this enabled, Alexa automatically detects what language a user speaks by analyzing the spoken wake word and proceeding utterances. Once Alexa identifies the language, all corresponding responses are in the same language. The current supported language pairs are:
 - `[ "en-US", "es-US" ]`
 - `[ "es-US", "en-US" ]`
 - `[ "en-IN", "hi-IN" ]`
 - `[ "hi-IN", "en-IN" ]`
 - `[ "en-CA", "fr-CA" ]`
 - `[ "fr-CA", "en-CA" ]`
<br/> **IMPORTANT**: Specify the locales your device supports in the [localeCombinations](https://developer.amazon.com/docs/alexa-voice-service/system.html#localecombinations) field in AlexaClientSDKConfig.json. This field can't be empty. If you don't set these values, the sample app fails to run.
* Added two new system settings, [Timezone](https://developer.amazon.com/docs/alexa-voice-service/system.html#settimezone) and [Locale](https://developer.amazon.com/docs/alexa-voice-service/system.html#locales).
    - Timezone: For example, you can set the `defaultTimezone` to `America/Vancouver`. If you don't set a value, `GMT` is set as the default value. If you set a new timezone, make sure that your AVS system settings and default timezone stay in sync. To handle this, use the new class `SystemTimeZoneInterface`. See [System Interface > SetTimeZone](https://developer.amazon.com/docs/alexa-voice-service/system.html#settimezone) for more information.
    - Locale: For example, you can set `defaultLocale` to `en-GB`, instead of the default `en-US`.
* The [SpeechRecognizer](https://developer.amazon.com/docs/alexa-voice-service/speechrecognizer.html) interface now supports the following functionalities.
  - Change wake word (`Alexa` supported for now).
  - Toggle start of request tone on/off.
  - Toggle End of request tone on/off.
* Deprecated the [CapabilityAgents](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1avs_1_1_capability_agent.html) `Settings{…}` library. `Settings {…}` now maps to an interface that's no longer supported. You might need to update your code to handle these changes. Read [Settings Interface](https://developer.amazon.com/docs/alexa-voice-service/per-interface-settings.html) for more details.
* Added support for three new locals: Spanish - United States (ES_US), Hindi - India (HI_IN), and Brazilian - Portuguese (PT_BR).
* Linked the atomic library to the sample app to prevent build errors on Raspberry Pi.

**Bug Fixes**

* Fixed resource leaking in [EqualizerCapabilityAgent](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1capability_agents_1_1equalizer_1_1_equalizer_capability_agent.html) after engine shutdown.
* [Issue 1391:](alexa#1391) Fixed an issue where [SQLiteDeviceSettingsStorage::open](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1settings_1_1storage_1_1_s_q_lite_device_setting_storage.html#a7733e56145916f7ff265c5c950add492) tries to acquire a mutex twice, resulting in deadlock.
* [Issue 1468:](alexa#1468) Fixed a bug in [AudioPlayer::cancelDirective](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1capability_agents_1_1audio_player_1_1_audio_player.html#a2c710c16f3627790fcc3238d34da9361) that causes a crash.
* Fixed Windows install script that caused the sample app build to fail - removed pip, flask, requests, and commentjson dependencies from the mingw.sh helper script.
* Fixed issue: notifications failed to sync upon device initialization. For example, let's say you had two devices - one turned on and the other turned off. After clearing the notification on the first device, it still showed up on the second device after turning it on.
* Fixed issue: barging in on a reminder caused it to stick in an inconsistent state, blocking subsequent reminders. For example, if a reminder was going off and you interrupted it, the reminder would get persist indefinitely. You could schedule future reminders, but they wouldn't play. Saying “Alexa stop” or rebooting the device fixed the “stuck” reminder.

**Known Issues**

* Music playback history isn't displayed in the Alexa app for certain account and device types.
* When using Gnu Compiler Collection 8+ (GCC 8+), `-Wclass-memaccess` triggers warnings. You can ignore these, they don't cause the build to fail.
* Android error `libDefaultClient.so not found` might occur. Resolve this by upgrading to ADB version 1.0.40.
* If a device loses a network connection, the lost connection status isn't returned via local TTS.
* ACL encounters issues if it receives audio attachments but doesn't consume them.
* `SpeechSynthesizerState` uses `GAINING_FOCUS` and `LOSING_FOCUS` as a  workaround for handling intermediate states.
* Media steamed through Bluetooth might abruptly stop. To restart playback, resume the media in the source application or toggle next/previous.
* If a connected Bluetooth device is inactive, the Alexa app might indicates that audio is playing.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation isn't yet supported.
* When using some products, interrupted Bluetooth playback might not resume if other content is locally streamed.
* `make integration` isn't available for Android. To run Android integration tests, manually upload the test binary and input file and run ADB.
* Alexa might truncate the beginning of speech when responding to text-to-speech (TTS) user events. This only impacts Raspberry Pi devices running Android Things with HDMI output audio.
* A reminder TTS message doesn't play if the sample app restarts and loses a network connection. Instead, the default alarm tone plays twice.
* `ServerDisconnectIntegratonTest` tests are disabled until they are updated to reflect new service behavior.
* Bluetooth initialization must complete before connecting devices, otherwise devices are ignored.
* The `DirectiveSequencerTest.test_handleBlockingThenImmediatelyThenNonBockingOnSameDialogId` test fails intermittently.

Changes in this update:

**Enhancements**

- Added support for SpeechSynthesizer v.1.2 which includes the new `playBehaviour` directive.  For more information, see [SpeechSynthesizer v1.2](https://github.com/alexa/avs-device-sdk/wiki/SpeechSynthesizer-Interface-v1.2).
- Added support for pre-buffering in [AudioPlayer](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1capability_agents_1_1audio_player_1_1_audio_player.html). You can optionally choose the number of instances MediaPlayer uses in the [AlexaClientSDKconfig.json](https://github.com/alexa/avs-device-sdk/blob/master/Integration/AlexaClientSDKConfig.json). Important: the contract for [MediaPlayerInterface](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1utils_1_1media_player_1_1_media_player_interface.html) has changed. You must now make sure that the `SourceId` value returned by `setSource()` is unique across all instances.
- AudioPlayer is now licensed under the Amazon Software License instead of the Apache Software License.

**Bug Fixes**

- Fixed Android issue that caused the build script to ignore PKG_CONFIG_PATH. This sometimes caused the build to use a preinstalled dependency instead of the specific version downloaded by the Android script (e.g - openssl).
- Fixed Android issue that prevented the Sample app from running at the same time as other applications using the microphone. Android doesn't inherently allow two applications to use the microphone. Pressing the mute button now temporarily stops Alexa from accessing the microphone.
- Added 'quit' (– q) to the settings sub menu.
- Fixed outdated dependencies issue in the Windows install script.
- Fixed reminders issue that caused Notification LEDs to stay on, even after dismissing the alert.

**Known Issues**

* Music playback history isn't displayed in the Alexa app for certain account and device types.
* When using Gnu Compiler Collection 8+ (GCC 8+), `-Wclass-memaccess` triggers warnings. You can ignore these, they don't cause the build to fail.
* Android error `libDefaultClient.so not found` might occur. Resolve this by upgrading to ADB version 1.0.40.
* If a device loses a network connection, the lost connection status isn't returned via local TTS.
* ACL encounters issues if it receives audio attachments but doesn't consume them.
* `SpeechSynthesizerState` uses `GAINING_FOCUS` and `LOSING_FOCUS` as a  workaround for handling intermediate states.
* Media steamed through Bluetooth might abruptly stop. To restart playback, resume the media in the source application or toggle next/previous.
* If a connected Bluetooth device is inactive, the Alexa app might indicates that audio is playing.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation isn't yet supported.
* When using some products, interrupted Bluetooth playback might not resume if other content is locally streamed.
* `make integration` isn't available for Android. To run Android integration tests, manually upload the test binary and input file and run ADB.
* Alexa might truncate the beginning of speech when responding to text-to-speech (TTS) user events. This only impacts Raspberry Pi devices running Android Things with HDMI output audio.
* A reminder TTS message doesn't play if the sample app restarts and loses a network connection. Instead, the default alarm tone plays twice.
* `ServerDisconnectIntegratonTest` tests are disabled until they are updated to reflect new service behavior.
* Bluetooth initialization must complete before connecting devices, otherwise devices are ignored.
* The `DirectiveSequencerTest.test_handleBlockingThenImmediatelyThenNonBockingOnSameDialogId` test fails intermittently.
* On some devices, Alexa gets stuck in a permanent listening state. Pressing `t` and `h` in the Sample App doesn't exit the listening state.
* Exiting the `settings` menu doesn't provide a message to indicate that you are back in the main menu.

Changes in this update:

**Enhancements**

- Added support for [captions for TTS](https://developer.amazon.com/docs/avs-device-sdk/features.html#captions). This enhancement allows you to print onscreen captions for Alexa voice responses.
- Added support for [SpeechSynthesizer Interface 1.3](https://developer.amazon.com/docs/alexa-voice-service/speechsynthesizer.html). This interface supports the new `captions` parameter.
- Added support for [AudioPlayer Interface 1.3](https://developer.amazon.com/docs/alexa-voice-service/audioplayer.html). This interface supports the new `captions` parameter.
- Added support for [Interaction Model 1.2](https://developer.amazon.com/docs/alexa-voice-service/interactionmodel-interface.html).
- Added support for [System 2.0](https://developer.amazon.com/en-US/docs/alexa/alexa-voice-service/system.html).
- Added support for Alarm Volume Ramp. This feature lets you to fade in alarms for a more pleasant experience. You enable alarm volume ramp in the sample app through the settings menu.
- Added support for using certified senders for URI path extensions. This change allows you to specify the URI path extension when sending messages with [`CertifiedSender::sendJSONMessage`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1certified_sender_1_1_certified_sender.html#a4c0706d79717b226ba77d1a9c3280fe6).
- Added new [`Metrics`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1utils_1_1_metrics.html) interfaces and helper classes. These additions help you create and consume [`Metrics`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1utils_1_1_metrics.html) events.
 - **Interfaces** - `MetricRecorderInterface`, `MetricSinkInterface`.
 - **Helper Classes** - `DataPointStringBuilder`, `DataPointCounterBuilder`, `DataPointDurationBuilder`, `MetricEventBuilder`.

- Added support for the following AVS [endpoint](../avs-device-sdk/endpoints.html) controller capabilities:
 - [Alexa.ModeController](https://developer.amazon.com/docs/alexa-voice-service/alexa-modecontroller.html)
 - [Alexa.RangeController](https://developer.amazon.com/docs/alexa-voice-service/alexa-rangecontroller.html)
 - [Alexa.PowerController](https://developer.amazon.com/docs/alexa-voice-service/alexa-powercontroller.html)
 - [Alexa.ToggleController](https://developer.amazon.com/docs/alexa-voice-service/alexa-togglecontroller.html)

- Added `PowerResourceManagerInterface`. This interface allows the SDK to control power resource levels for components such as the `AudioInputProcessor` and `SpeechSynthesizer`.
- Added `AlexaInterfaceCapabilityAgent`. This Capability Agent handles common directives and endpoint controller capabilities support by [`Alexa.AlexaInterface`](../alexa-voice-service/alexa.html).
- Added `AlexaInterfaceMessageSenderInterface`. This interface is required to send common events defined by the `Alexa.AlexaInterface` interface.
- Added `BufferingComplete` to [`MediaPlayerObserverInterface`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1avs_common_1_1utils_1_1media_player_1_1_media_player_observer_interface.html). This method helps improve performance in poor networking conditions by making sure `MediaPlayer` pre-buffers correctly.
- Added `SendDTMF` to `CallManagerInterface`. This method allows you to send DTMF tones during calls.

**New build options**

- CAPTIONS
 - **ADDED** [`CAPTIONS`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#captions)
 - **ADDED** [`LIBWEBVTT_LIB_PATH`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#captions)
 - **ADDED** [`LIBWEBVTT_INCLUDE_DIR`](https://developer.amazon.com/docs//avs-device-sdk/cmake-parameters.html#captions)
- METRICS
 - **ADDED** [`METRICS`](https://developer.amazon.com/docs//avs-device-sdk/cmake-parameters.html#metrics)
- ENDPONTS
 - **ADDED** [`ENABLE_ALL_ENDPOINT_CONTROLLERS`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#endpoints)
 - **ADDED** [`ENABLE_POWER_CONTROLLER`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#endpoints)
 - **ADDED** [`ENABLE_TOGGLE_CONTROLLER`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#endpoints)
 - **ADDED** [`ENABLE_RANGE_CONTROLLER`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#endpoints)
 - **ADDED** [`ENABLE_MODE_CONTROLLER`](https://developer.amazon.com/docs/avs-device-sdk/cmake-parameters.html#endpoints)

**New dependencies**

- To use captions, you must install a [new dependency](https://developer.amazon.com/docs/avs-device-sdk/dependencies) – the [libwebvtt parsing library](https://github.com/alexa/webvtt). Webvtt is a C/C++ library for interpreting and authoring conformant WebVTT content. WebVTT is a caption and subtitle format designed for use with HTML5 audio and video elements.

**Bug fixes**

- Fixed [`MimeResponseSink::onReceiveNonMimeData`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1acl_1_1_mime_response_sink.html) [data issue](alexa#1519) that returned invalid data.
- Fixed [data type issue](alexa#1519) that incorrectly used `finalResponseCode` instead of [`FinalResponseCodeId`](https://github.com/alexa/avs-device-sdk/blob/master/AVSCommon/Utils/src/LibcurlUtils/LibCurlHttpContentFetcher.cpp#L370).
- Fixed [`UrlContentToAttachmentConverter`](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1playlist_parser_1_1_url_content_to_attachment_converter.html) issue that used the incorrect range parameter.
- Fixed `FinallyGuard` [linking issue](alexa#1517) that caused problems compiling the SDK on iOS.
- Fixed a [Bluetooth Capability Agent](https://alexa.github.io/avs-device-sdk/classalexa_client_s_d_k_1_1capability_agents_1_1bluetooth_1_1_bluetooth.html) bug that prevented devices from initializing.

**Known Issues**

* The WebVTT dependency required for `captions` isn't supported for Windows/Android.
* Music playback history isn't displayed in the Alexa app for certain account and device types.
* When using Gnu Compiler Collection 8+ (GCC 8+), `-Wclass-memaccess` triggers warnings. You can ignore these, they don't cause the build to fail.
* Android error `libDefaultClient.so not found` might occur. Resolve this by upgrading to ADB version 1.0.40.
* If a device loses a network connection, the lost connection status isn't returned via local TTS.
* ACL encounters issues if it receives audio attachments but doesn't consume them.
* `SpeechSynthesizerState` uses `GAINING_FOCUS` and `LOSING_FOCUS` as a workaround for handling intermediate states.
* Media steamed through Bluetooth might abruptly stop. To restart playback, resume the media in the source application or toggle next/previous.
* If a connected Bluetooth device is inactive, the Alexa app might indicates that audio is playing.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation isn't yet supported.
* When using some products, interrupted Bluetooth playback might not resume if other content is locally streamed.
* `make integration` isn't available for Android. To run Android integration tests, manually upload the test binary and input file and run ADB.
* Alexa might truncate the beginning of speech when responding to text-to-speech (TTS) user events. This only impacts Raspberry Pi devices running Android Things with HDMI output audio.
* A reminder TTS message doesn't play if the sample app restarts and loses a network connection. Instead, the default alarm tone plays twice.
* `ServerDisconnectIntegratonTest` tests are disabled until they are updated to reflect new service behavior.
* Bluetooth initialization must complete before connecting devices, otherwise devices are ignored.
* The `DirectiveSequencerTest.test_handleBlockingThenImmediatelyThenNonBockingOnSameDialogId` test fails intermittently.
* On some devices, Alexa gets stuck in a permanent listening state. Pressing `t` and `h` in the Sample App doesn't exit the listening state.
* Exiting the settings menu doesn't provide a message to indicate that you're back in the main menu.

Changes in this update:

**Enhancements**

* Added support for [Bluetooth Interface 2.0](https://developer.amazon.com/docs/alexa/alexa-voice-service/bluetooth.html). This interface adds support for multiple simultaneous connections to Bluetooth peripherals.
* Added support for [Audio Focus Manager Library (AFML) Multi Activity](https://developer.amazon.com/docs/alexa/avs-device-sdk/sdk-interaction-model.html). This interface enhances the behavior of a device so it can handle more than one Activity per Channel.
* Added the `obfuscatePrivateData` logging method to help remove certain data from logs.
* Updated `MediaPlayerObserverInterface` to include metadata about playback states.
* Added SDK extension point. You can integrate CMake projects into the SDK without cloning those projects into a subdirectory.

**Bug fixes**

* Fixed Mac/OSX issue that caused an unresponsive Sample App when not connected to the internet.
* Fixed issue that prevented sample app from exiting various states.
* Fixed `UIManager` issue that caused an error in the logs when the device with built without the wake word enabled.
* Fixed volume issue that caused timers to ascend in volume when setting up ascending alarms.
* Fixed alert volume issue that caused any changes to the alert volume to notify observers.
* Fixed EQ issue where changes to the EQ band levels didn't notify observers.
* Fixed Bluetooth bug that caused short notification sounds from a connected phone to stop audio playback on the device.

**Known Issues**

* Build errors can occur on the Raspberry Pi due to incorrect linking of the atomic library. A suggested workaround is to add the following `set(CMAKE_CXX_LINK_FLAGS "${CMAKE_CXX_LINK_FLAGS} -latomic")` to the top most CMake file.
* The WebVTT dependency required for `captions` isn't supported for Windows/Android.
* Exiting from the setting option takes you back to the Options Menu directly. It doesn't provide a message to indicate that you're back in the main menu.
* Failing Unit Tests and AIP Unit tests are disabled on Windows
* `AudioInputProcessor` unit tests don't build on Windows when with the `-DCMAKE_BUILD_TYPE=DEBUG` cmake parameter.
* Music playback history isn't displayed in the Alexa app for certain account and device types.
* When using Gnu Compiler Collection 8+ (GCC 8+), `-Wclass-memaccess` triggers warnings. You can ignore these, they don't cause the build to fail.
* Android error `libDefaultClient.so not found` might occur. Resolve this by upgrading to ADB version 1.0.40.
* If a device loses a network connection, the lost connection status isn't returned though local TTS.
* ACL encounters issues if it receives audio attachments but doesn't consume them.
* Media streamed through Bluetooth might abruptly stop. To restart playback, resume the media in the source application or toggle next/previous.
* If a connected Bluetooth device is inactive, the Alexa app might indicates that audio is playing.
* The Bluetooth agent assumes that the Bluetooth adapter is always connected to a power source. Disconnecting from a power source during operation isn't yet supported.
* When using some products, interrupted Bluetooth playback might not resume if other content is locally streamed.
* `make integration` isn't available for Android. To run Android integration tests, manually upload the test binary and input file and run ADB.
* Alexa might truncate the beginning of speech when responding to text-to-speech (TTS)  user events. This only impacts Raspberry Pi devices running Android Things with HDMI output audio.
* A reminder TTS message doesn't play if the sample app restarts and loses a network connection. Instead, the default alarm tone plays twice.
* `ServerDisconnectIntegratonTest` tests are disabled until they are updated to reflect new service behavior.
* The `DirectiveSequencerTest.test_handleBlockingThenImmediatelyThenNonBockingOnSameDialogId` test fails intermittently.

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html)

Changes in this update:

- Fixed a bug that caused Display Cards for certain EMP adapters to stop rendering.

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html).

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html).

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html).

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html)

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html)

Changes in this update:

Feature enhancements, updates, and resolved issues from all releases are available on the [Amazon developer portal](https://developer.amazon.com/docs/alexa/avs-device-sdk/release-notes.html)