How do I prevent Apple TV from reducing frame rate after a while?

I am developing a photoalbum kind of app with moving objects. The problem is, that after a while 5 minutes or so framerate drops and animation starts to stutter. As soon as I press one button on the remote it works for another 5 minutes fluently. I turned of screensaver and set sleep to OFF.

So I assume there is something telling apple tv, that nobody is using it. Is there a switch/setting somewhere to prevent that?