goes back to home screen after 3 minutes

[NightStalker]

I have a Samsung tablet it goes back to home screen after 3 minutes. I have done a hard reset.turned off apps running in background. Turned of power saving mode. Set do not time out until 30 minutes of inactivety. I have the latest updates. It is running on jelly bean 4.1.2. Is there anything else I can do to keep the screen on while I am watching something?

 

[Golfdriver97]

What are you watching? YouTube videos?