Hi everyone, I've just downgrade my iPhone 3G from 4.0 to 3.1.3 last night. But this morning, there's seems to have some problems with the screen. When I tap, the screen does the actions like I hold. For example, I play Asphalt 5, I tap to turn a little bit and then release right away, but the car still turns, even thought that I've released my thumb off the screen. Not just in game, everything else like that. When I tap, it holds. It's so annoying. Is there anyone can help me with this problem? Please reply if you know how to solve it, or even you know where the problem is.