I have more information.
Output Device Headset - WF-1000XM4 gives stereo for all 4 options.
Output Device Handsfree - WF-1000XM4 gives mono for all 4 options.
While clicking Test for Output Device Handsfree - WF-1000XM4 gives noise for
all 3 options, it actually does work, when I tried Google Meet inside Google
Chrome. And I am able to simultaneously select
Output Device Handsfree - WF-1000XM4
Input Device Handsfree - WF-1000XM4
and get audio input and output in Google Meet inside Google Chrome.
I haven't tried all 3 codec options yet.
I haven't tried other programs yet.
Still, under buster and bullseye, I was able to get stereo audio output
simultaneous with audio input with Sony WF-1000XM4 bt. Now, I can only get
mono audio output simultaenous with audio input.
Jeff (http: //engineering.purdue.edu/~qobi)
