I thought I just had a crappy headset, but as it turns out: Kubuntu/pulseaudio just has no support for Bluetooth HFP 1.6 :(
@daniel_bohrer
Yeah, have a similar setup currently but wanted something really portable. I ordered one of these Bluetooth audio card dongles. Hope that's a workaround :/
@bleeptrack @daniel_bohrer I bought a 2.4 GHz based headset (Arctis series pro wireless) just because of the Bluetooth issues and I'm super happy with it. Since the Dongle is always connected (even if the headphones are off) there are never issues with selecting the correct device.
@bleeptrack (for reference, more info here, starting at comment 25: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1838151 )
@bleeptrack yeah, this bugs me a lot too :-( currently I'm using the usual A2DP profile with a cable mic via audio jack as a fallback, but it's everything else than hands-free :/