After updating from version 6.9 to 6.10 on the shiftphone 8.1 the microphone in voice calls started just sounding self amplifying, increasingly loud and distorted, making it unusable for calling.
It sounds normal in a voice recording app. But with any app involving voice calls this happens. It resembles the sound of what happens when a microphone listens to what it just recorded from the speaker, even though this doesn’t appear to be what’s actually happening since the micphone wouldn’t be able to detect the sound of the speakers in another location or when I’m wearing headphones when I tested this, yet it still sounds that way despite that