Recently i switched from Manjaro gnome to Kde plasma and had a problem with bluetooth headset (Soundcore Q30).
I had a search in forum and found that pulseaudio should be replaced with manjaro-pipewire for better audio experience. So i remove pulseaudio from pamac (every package manually) and then installed manjaro-pipewire.
But still the problem exists, the sound quality is awful sometimes. So i have to unpair the device, reboot the system and do everything again when this happen.
Today i found out the problem is with bluetooth profiles, this awful mono sound comes from HSP/HPF profile and there is no profile with SBC or anything else.
in the end, sorry for my bad english 