windows_bt_baseband_av_mod

Description

Baseband modification for Windows to switch the Major Device Class to Audio/Video.

This registry modification switches Windows 10 to present itself as an Audio/Video device. This can be useful for bluetooth audio transmitters that refuse to pair to anything but devices that identify their main function as Audio/Video to enable these devices to stream Audio to Windows 10 (Note: Windows 10 version 2004 or higher is required for remote playback).

Installation

Download audio_video_bt.reg:

1. Right-click the link and Select Save target as or Save link as:
2. Then run the file to add the modifications to your Windows Registry.

Uninstallation

Download audio_video_bt_del.reg:

1. Right-click the link and Select Save target as or Save link as:
2. Then run the file to add the modifications to your Windows Registry.

Known Devices that Benefit

• HomeSpot Bluetooth 5.0 Audio Transmitter Adapter with USB C Connector

Additional Notes

• The COD Major and COD Type registry entries don't appear to behave exactly as documented by Microsoft. I surmise that these entries have rarely been utilized as of this writing since they appear to be buggy.
  • COD Major entry appears to be ignored if COD Type entry exists.
  • COD Type will actually result in bits 8 and bit 9 of the baseband (part of the Major Device Class) being set if the registry entry is a value above 7F (hex) and below 100 (hex). COD Type is suppose to only set the Minor Device Class according to the documentaiton.
  • COD Type values higher than FF (hex) (an invalid number) will result in COD minor class being set to 0, not 1 (COD_COMPUTER_MINOR_DESKTOP) as MS indicates in the documentation.
• Android applications that display COD can be used to aid in debugging which type is returned for which value.
• The same type of baseband modification will work for Linux's bluetooth stack as well. But, I was unable to get the Linux A2DP sink role to work reliably during my testing with Linux.