libusb_control_transfer returns error.

[JAicewizard]

While debuging OpenCorsairLink I noticed that within the corsairlink_asetek_init function the first libusb_control_transfer returns -9 (LIBUSB_ERROR_PIPE) while the second doesn't.
What startled me even more what that this is only dependent on the request and the value.

Since you commented out the error handling for this error, I hoped you would know why this might happen. I am using a h100i pro, the git commit for the comment was a fix for h150i pro, is this that * pro devices arn't supposed to have this and non pro devices do need it?

I am currently trying to write a simple kernel driver to control my AIO, mostly for fun, and I hit the same error (EPIPE, or pipe error).