Whenever I am playing movies for long periods of time 30min-45mins and then have to pause the movie, I have found that I can't because the touch screen doesn't respond to my touch. It starts responding again after I press the home button then go to the iPod app to watch the movie again. It responds if I pause the movie every 15mins. How should I fix this? Should I go to an apple store? I have a 32GB 3GS, 3.0. I restored but I still have the problem.