I had the same problem on my Lenovo IdeaPad Flex 5 14IIL05 running Windows 11. I have tried updating drivers, several other headphones but nothing worked.
Only thing worked for me was the instructions on below link. Although it says the instructions for windows 10 it worked for me. My value was set to 1 and I have changed it to zero. (step 5)
https://winaero.com/enable-or-disable-bluetooth-absolute-volume-in-windows-10/
- Open the Registry Editor app.
- Go to the following Registry key.
`HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Bluetooth\Audio\AVRCP\CT``` - On the right, modify or create a new 32-Bit DWORD value DisableAbsoluteVolume.
Note: Even if you are running 64-bit Windows you must still create a 32-bit DWORD value. - Set its value to 1 in to disable the Absolute Volume feature.
- Set its value to 0 in to enable Absolute Volume.
- Restart computer.