When using the recorder app with my fairphone 4 there is no option to decide the input device (bluetooth or internal mic) it is always the internal microphone.
I expect it to always use the bluetooth mic if connected.
When calling with the calls app, the bluetooth mic is used.
When calling with signal or whatsapp, the internal is used as well.
It did not help though to use any of the available..? I guess that the mic is used for aptX only, as I remember it working a while a go with a different headset?
Any experience from fairphone4 users running iodeOS here?
I would guess (??) this to be a bug / issue with the specific headset, do you have any other bluetooth headsets to test with?
Possibly some searching on Lineage OS Sony WF-1000XM5 would yield some results with a bit better sleuthing than my quick search came up with (I see some comments for other devices and other headsets).