when I make a normal voice call, the sound feels good. if you go into external speaker mode you always feel good. but when I go back to the internal speaker I hear a strange noise of interference ... as if the audio is not well calibrated and is too loud.
time ago I reported a problem during calls that still has not been resolved: when I make a call and first step into speakerphone and then go back to the normal speaker you hear strange noises. the sound is not calibrated. in fact if I go in the hidden menu of the settings and I do the calibration no longer feel or even if I turn it off and on again.