Let's work on this audio issue tthede! Next time you make or receive a call please push the up volume while on the call and see if this makes it better. I also recommend reprogramming your iPhone 4 by calling *228 and select option 1, then power off/on at the end of the call. Keep us posted.
AntonioC_VZW Follow us on Twitter at www.twitter.com/VZWSupport