Here's the situation. Twice now, my iPad has become unresponsive, usually after being asleep, with the cover closed, for a couple of hours. I open the cover to a black screen. The ipad does not respond to either the Home button or the Sleep/Wake button. It also does not respond to a hard reset (Sleep/Wake button and Home button held down for 30 seconds). It ONLY responds if I plug it in to my PC. Running IOS 5. The battery IS NOT dead, in fact the first time it happened battery charge was at over 90%. I also checked the toggle switch on the side to make sure it wasn't set to ignore key presses. Clearly, this is unacceptable. It's a mobile device and I need to be able to depend on it when away from the office. As it is, it's a $600 paper weight.