Black Rectangles on 42" Vizio HDTV LCD

Question

Small black rectangles appear on my screen at various times and places, sometimes if I turn off the direct tv they go away, or if I turn the tv off and then on again...not sure if it's the tv or direct tv?? I've also had time when I turn the tv on and the whole screen stays black or half the screen will...any advice would be greatly appreciated.