I have my Sharp Aquos hooked up to DirectTv HD Dvr box. Everything works fine except: without touching any remote, tv will show the input options on the right side of the screen and then slowly start Scrolling through input options. When I use the DirectTv remote, I can make it go back to input 4 which is the hdmi input. Why is this happening? Do I have neighbor with same tv and he is changing inputs and my tv reads his remote? Is there a way to lock my tv that I dont know about? Help