Ever since my EE4 update, my earpiece sounds much more "buzzy" when people call. I much preferred the way things sounded when I first had my phone. I've noticed this has been true whether I'm talking to someone on a landline, a VZW phone, or another carrier's phone.
I noticed mine has really tinny and crackly sound in the ear piece as well. Dunno what that's all about. I'm gonna try turning off noise suppression and see if that helps.
Mine may have changed a bit. I have noticed a couple of times it seemed like I have turned down the volume when I did not. I may try to change the privacy mode if I have any problems.