Have you checked your settings for "Keep device awake while/when charging"? I'm not sure if it is under "Power", "Display", or "Security". You may also what to look under "Display" for "Timeout" and set it to a length longer than your show or "Never". Some devices do not have the "Never" option if they have the "Keep device...." option. There are also apps that can control your screen timeout issue. Check the market.