No picture when I plug my ipod touch into my tv with HDMI cable?

I have the ipod adapter for the hdmi cable. I have the 4th generation ipod touch. The movies will play from the video app just fine, I get both audio and video.

But when I go to the Youtube app, I only get audio, no picture. Why is this? Can it be fixed? In my videos setting on my ipod touch, there is no option for tv.