the sound quality on calls is poor on my 4s.
When I call someone or they call me, the quality of the sound is poor. The volume seems quite low and the sound rattles at times. Is there a fix or is it a hardware issue. I had another iphone 4s that Apple replaced for the same peoblem before (my son's phone).
iPhone 4S, iOS 6.0.1, modem firmware 3.0.04