In my opinion, what's happening it's a restart of a system service. However, I am not an expert. Whenever I watch a movie on netflix, youtube or I drive with google maps in full screen, every 5 minutes or so, the app which is in full screen minimizes in the right bottom corner, as like I was pressing the home button, which I definetly don't. The screen also flickers when this happens, like a milisecond, you can barely notice it. It happens while typing a text message, the text input gets deleted and the keyboard app restarted (I believe). I haven't tried any other keyboards. I use Samsung keyboard, but I think that's irrelevant as it doesn't seem to be only the keyboard. As I said in my previous post, I used Youtube in Safe Mode and the problem persists. It minimeses by itself every few minutes.