In wip0.16 I spotted a serious problem.
Today it happened multiple times. Somebody called me and we didn't hear each other.
It works when I make a call, but it isn't always when I get a call.

Plus during the call I switched to the loudspeaker, and from this point the phone was randomly automatically switching between the ear piece and the loudspeaker. Hmm.
It seems need to go back to the drawing board.

Edit: In this minute my phone just started to play the ringtone. The screen was blank and there was no incoming call. I couldn't stop the phone playing the ringtone because seemingly there was no reason why it started.
I restarted the network but didn't help. I needed to restart the phone to get rid of it. Strange. Oh my, I thought I had only the video recording to fix.