First I noticed that while playing games. I thought it was sound/music related, heat related, etc. But then, I saw it rebooting by itself while no one was touching it. I even closed the game and locked the screen. But it still reboots randomly.
Hold power and volume down for 15 seconds - wait until vibrate then release.
In case others do not know, the above step is hard reset, which will wipe out all contents and apps on your phone.
I had the reboot problem but it was a loose battery. Since you said no one touched it though it could be something else. I tried the paper at the end the battery trick and no more reboots. BTW just placing the phone down sometimes would make it reboot so are you sure there were not table bumps or vibrations?
Very interesting. I tried the paper trick too two days ago. And I have not had a reboot since! I am not sure if it was really loose battery, or by pulling the battery out it cleared something.
Well, it rebooted again tonight while I was playing a game. And wiped out all my progress in that game.:angry: