Hi everyone,
I'm not so sure if this bug is firmware dependent.
I've two different PCs, in the same chamber, with the same BT adapter (with intel AX200), and very very close to an LG micro stereo.
The older PC has, in two different partitions, Siduction (a Debian Sid derivative with KDE) and Debian Bullseye Stable XFCE (+ Blueman) with latest kernel from backport. Both systems pair very well with stereo: I have not done prolonged texts, but everything seems to work very well and only in certain cases, after reboot, I have to delete the BT profile and recreate it again.
In my main pc, with Gnome, the first time I tried the system paired with the stereo, but now, every time I try, the pairing works for an instant, but it stops immediately. It's definitely not a hardware problem, as the system works fine on Windows.
I also tried to install latest firmware from Sid, but it still gives the same issue.
In conclusion, I think the problem somehow lies with Gnome. :-(
Best regards and happy holidays to all!
Domenico