I had no prox sensor issues prior to this update. Now my prox sensor is absolutely CRAZY. It flickers on and off the whole time I'm on the phone. This whole situation is pretty ridiculous. I had a suspicion that an attempt to fix what is most likely a hardware issue with some phones would likely cause phones that were previously fine to malfunction. And it looks like it's happened. Is there any way to downgrade from 4.1 to 4.0 without having previously jailbroken the phone?