I have a problem with my Panasonic TH-42PW6. When playing an RGB signal thru SCART into the tuner box, it causes the picture to jump slightly. It does it with Sky or DVD. Playing a DVD thru component signal (3 RCA) is fine, but my Sky+ box doesnt have component out, only SCART. When you have the Sky+ box set on PAL, the picture doesnt jump but the quality isnt as good. Could there be a fault with the tuner box, or is it something simple?