My less than a week old white iPhone 4 is already having problems. About the 4th day i had it, it began to shut off and reboot itself maybe 1-2 times a day. Now, it does it as often as every couple of minutes, and sometimes it wont even turn back on for an hour or so. I've tried to restore it multiple times, but the phone shuts off before it can ever come close to finishing. If i have the phone open when it shuts off, the screen fades away to black, sometimes with a red or yellow horizontal line across the screen. Other times it shuts off in my pocket or wherever. Like I said, this phone is BRAND new. Any ideas on whats wrong with the thing?