my dad has a lg 42px5d plasma tv connected to a sky hd box.when switching to the hdmi channel and playing a hd channel the picture appears for about 5 minutes then dissappears displaying `no signal` and a black screen.does anybody know if this is a tv fault or a sky hd box fault.it is connected via scart and hdmi.

ta

I have the same TV, do you have any other HDMI HD signal to test like a Blue-ray or HD DVD player, it could well be the Sky HD box. ring sky & report it as a fault & let them come out & replace the box you would prob find out then.

You could even try another HDMI cable if you haven't already.