Built-in microphone feed off-center (DC offset)
Since I believe BM818 applies some gain by itself, I guess this contributes a lot to the perceived distortion on the other side of the call, since off-center audio will get clipped much sooner.
Since I believe BM818 applies some gain by itself, I guess this contributes a lot to the perceived distortion on the other side of the call, since off-center audio will get clipped much sooner.