This is a discussion on My iPhone 4 wont turn on! within the iPhone Help forums, part of the iPhone Forum category; Please note that this is a pretty new phone. I got it recently, maybe a couple months ago.
I've always taken good care of this ...
I also have the same problem. I just got a new iphone 4 from the Apple store. When the phone is idle for 2 to 3 hours, it shuts by itself. Then I had to press the power button and the home button together and hold it for a while to reboot the phone. This happens every time the phone is idle for two to three hours.
I wonder Apple compromised the quality due to a mass production of iPhone 4??
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