Sounds were not added to category 'ui-sounds'.

[pixelzoom]

This is a prerequisite to implementing the proposed fix in #77 (comment).

When sound was added for vegas components in #89, they were apparently not assigned to category 'ui-sounds'. Reproducible by adding this to a sim with a Game, like Equality Explorer:

soundManager.setOutputLevelForCategory( 'user-interface', 0 );

This should turn off all 'ui-sounds'. But some vegas sounds continue to play. (GameAudioPlayer sounds are expect to play - those are not the sounds we're tallking about here.) This is definitely a problem for LevelSelectionButton, and the "back" button in the scoreboard. I don't recall what other sounds were added in #89, but it's probably a problem for them too.

[jbphet]

I've added the level selection and back buttons into the "user-interface" sound category. I tested it by adding code to set the output level for this category to zero in equality-explorer-main.js, and it seemed to behave as descired.

Assigning to @pixelzoom to review and to cherry-pick into an RC for which this change is needed.

[pixelzoom]

I verified that this is working as desired in Equality Explorer. I'll leave self-assigned until we decide how to address #77, which will determine whether I need to cherry-pick for phetsims/equality-explorer#177.

[pixelzoom]

I've completed the cherry-picks for phetsims/equality-explorer#177. Closing.