Default [Q] Invisible app

Hi guys,
I've just recently bought the Tab Pro 10.1", and I'm very happy with it, but I do have quite an annoying issue, sometimes my screen becomes unresponsive, except on the statusbar, I can use the hardware keys and go back to my homescreen, but the screen continues to be unresponsive, as if some app is invisible... Anybody have an idea on how to fix this?