Anyone know how to fix that? Here's what I've unsuccessfully tried so far:
I turned off Bluetooth and WiFi.
I've had every single iPhone version and also used every one on my same car radio (who can afford a new car when you spend so much money with Apple?). My next step I guess would be to dust off the prior iPhone 4 I had and to see if that now has background noise now that it is on iOS 5, in which case maybe it is a software issue not a hardware issue.
But I'd rather get a magic answer from someone here. If Apple Support community response rates were my batting average, I'd be batting about .100 right now.
iPhone 4, Mac OS X (10.7.2), It's an iPhone 4S not 4