HTC Rezound

So I have an Incredible and a Rezound and the audio on the Rezound sounds like I am underwater. Any idea what's going on? No one wants to talk to me unless I call them back on the Incredible.

Tech support had me erase phone storage and then told me not to install any apps or restore my apps to see if that fixes the trick. It didn't. Now they are sending me a new Sim Card. He says my old one might be corrupted and causing the problem.