Just recently this started happening to me. It sounds exactly like that pulsating buzzing sound you get when a GSM phone is near a set of old computer speakers... but it happens in my earpiece and for the entire phone call. Its so loud and annoying sometimes that I have to put it on speakerphone to talk because its unbearable... Its completely random, so at the apple store today I couldnt duplicate it, and was denied a replacement for that, and for a cracking case. (Never dropped the phone). Anyone else have the buzzing issue?