My Droid Charge randomly restarts throughout the day, sometimes while I'm using it, sometimes while it's just sitting on the table. I've reset it twice this week. After the second reset, I left it alone, no apps, no calendar, no email, nothing. It restarted itself twice with a few hours. Is this what I should expect? This is my first smartphone, so I don't have anything to compare to. Is there anything else I should try?