@tim474,
When it doesn't work, please run amixer contents to check Input Source/Capture Source value, if its value is "Headset Mic"? If it is, it means the pulseaudio's behaviour is correct, maybe the kernel driver has some problem on your machine.
@tim474,
When it doesn't work, please run amixer contents to check Input Source/Capture Source value, if its value is "Headset Mic"? If it is, it means the pulseaudio's behaviour is correct, maybe the kernel driver has some problem on your machine.