I just bought the tab s 10.5 and I put a few movies on it and the only 2 times I have watched a movie it does this. After about 45 min I can hear the sound like when I hit the back button and it backs out of the movie and then it backs out of the app completely. My hands are nowhere near the tablet and it just does it on its own. If I try to open the movie back up it continues to back out. It does this with any app open and also when it is just sitting on the home screen. I have to turn it off for a while and then it will work. This has happened twice now and both times I was on the treadmill. Not sure if that has anything to do with it. I am going to see what happens if I try and watch a movie at home now. Has anyone experienced this?