My phone has been initializing MTP when not plugged in. Sometimes it even thinks it is charging when it is not (it shows the little charging animation in upper right screen). At about the same time, it will go into Car Mode. This was happening all last week, eating up battery pretty heavily. Shutting it down didn't help. It would start itself. So i reset to factory settings Sunday. This seemed to help for a day or two but I just now see it is doing it again. Any clues to what might be happening here?