Help! My wife's D3 locks immediately after starting a call. She has to hit the power/sleep button to wake it up to end the call. Anyone know how to stop this? She says she has not changed any settings and my D3 has never done this. Don't see any new apps installed and the phone has been rebooted. (Also, it locks while holding it, not anything to do with the proximity sensor!) Not a good thing when she has to look at the phone when driving!!! Please help! Thanks!!