Video output will not work on iPad.

My iPad2 is supposed to "mirror" when connected to a monitor or TV when playing videos. It does not - I get a blank screen on the TV once the video begins. It mirrors before the video but once the video plays, it will only play on the iPad. Sound comes through fine. What is the problem? I have tried 2 TV's with the same result. This occurs with both Netflix and Amazon streaming videos.