I have iphone 4 since launch day. home button stopped working sometimes. Got a replacement. With this one, stock apps crashed all the time. Restored several times, still had the issue. Swapped it. Second replacement is great. Except I've hit the mute button with my face I think three times now. I thought the first two I was juggling the phone on my shoulder but now I'm beginning to think the sensor gets tripped up when I'm outside or near sunlight (near a window). Restored it after I thought it did it twice from juggling it on my shoulder. Just did it again today when I swear I had the phone up to my ear the whole time for the six minutes. I can see the red sensor in a dark room but it seems dimmer than my original iphone 4. Thoughts? replace again? I have no time to deal with pretentious genius bar people. If I need to swap it again, I think I'm going to call Apple Support. But what are your thoughts???