Answers checklist.

• I have read the documentation ESP-IDF Programming Guide and the issue is not addressed there.
• I have updated my IDF branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

General issue report

I'm trying to implement the volume callback for uac_set_volume_cb_t

I can't find anywhere in the docs or code what the units of the volume are.