If I leave my iPhone without an fingers on the screen, the screen will become unresponsive after a few seconds. It is not frozen, and locking and unlocking unfreeze it, as well as tilting in safari,terminal, or any other app that supports tilting. I have tried restoring, but it still does it, even before I jailbroke it. I think the screen may be sleeping or something to save power. Is there some way to disable this kind of powersaving, or is there no fix for this. I don't want to get it replaced or repaired, so any suggestion would be helpful.