[clort]

My information may be a little out of date, but in Bluetooth there was two types of audio. There is isochronous streaming (Headset profile) and audio streaming (Audio Profile). The Headset profile is bidirectional and time-sensitive (packets will be dropped if they take too long), it was designed for headsets as per its name ("communication device") rather than the Audio profile which, although it can be a source or a sink is basically for streaming, where the audio is not time-sensitive as such.

So yeah, the isochronous streaming mode is much lower bit rate but thats probably why Windows sets it as a communications device, because it needs that mode.

Its difficult to know exactly, but I use a Logitech Zone Vibe 125 headphones with microphone and find it works fine for phone calls and listening to audio. However, I am not an audio nerd and neither are the people I speak to using it. I never had any luck with in-ear devices.

[viraptor]

The best you can do these days while keeping to the standard is to use mSBC codec which at least does bidirectional 16bit. It's not too common unfortunately. At least on Linux you can force the codec you want with pipewire. On Mac you just get whatever Apple decides you're allowed.

[jeroenhd]

mSBC is kind of a hack, though. It pushes Bluetooth beyond its specifications and often works, but in my experience it also often causes dropped audio in less than ideal situations (i.e. walking with a Bluetooth headset on).

mSBC is worth a try if you haven't already tried it, but it's not a real solution. Bluetooth LE Audio does provide a fix, but real hardware that supports it is hard to come by.