Yes, it has to do with the proximity sensor issue. The most current update was supposed to fix it, however I still have issues with it as well as some of my friends. I have to say that it is MUCH better now, by only putting people on speaker phone or mute, rarely I hang up on someone now. You can try taking it to the Apple store, but they told me I would have to reproduce the issues (which I was unable to do standing in the store) before they would even think of looking into it deeper. I've read others just took it in to an Apple store and got theirs replaced. Good luck!!