I have a bluetooth headset which I use for work calls. I noticed that, on Linux, bluetooth headsets have two modes: high fidelity, where the audio is high quality but the mic is disabled; and handsfree, where the audio is lower quality, but the mic works.
In my current machine, which is an old, beat up laptop where I run tumbleweed, high fidelity mode works without issues, but I get no audio on handsfree mode. It’s been like this for a while, both Plasma and GNOME have this issue.
I also own a desktop and have no issues there. There are two main differences between the two machines: the desktop runs Debian and I don’t have a working audio card on the laptop.
Also nice to see the KDE Som settings window and how you change the profile of the speakers. As far as I see there are also multiple profiles for the microphone, did you try them?
Can you run (install if needed) audacity?
Try to hit the record button and watch the Recording Meter:
Mine gives a pop when recording is started. You can select different Audio sources using the Audio Setup menu.