Hi
I've been reading this thread with interest as I have been suffering from the same issue. I have now managed to solve it in a manner which I find slightly disturbing. I tried system restores via itunes as well as different jacks etc however
When I hold the phone against my right ear/cheek I get interference, when I switch to the left I do not. I have metal plates on my right cheek bone as a result of a broken cheek bone :s if this is obvious to others then fair enough but it kinda freaked me out a bit !
Tim