Why does my TV go black but still play sound?

TV sound delay with comcast cable?

• first off i have a 20" lg lcd tv (dont know which model but it was pretty expensive for a 20") and i have never watched tv on it untill 10 days ago when i got my comcast digital cable. its hooked up to the receiver through HDMI. The picture has always been 1-2 seconds ahead of the sound since installed. When i called comcast they had absolutely had no idea what i was talking about, they even put me on hold to go ask a higher up. Today a technition came to look at the setup. He gave me a brand new box, brand new HDMI cables, and brand new Component cables... Still sound lag... he told me that if the new box/cables didnt fix it, then it was my TV, and that this problem would be covered under its warranty. When i play xbox 360 the sound is fine.... so is comcast bs'ing me or might it really be my tv? I have a 5 year, money back guarentee so i dont care if i have to take it back or not. need experts help =)

• Answer:

  It's your TV. Contact the manufacturer for help. These new HD TVs have a lot of digital processing going on in them and it is possible that the sound can get out of sync due to manufacturing defects OR, there is a setting that lets games work better, which if you don't shut that off, it'll mess with your TV viewing of ordinary cable or broadcast TV. If you don't have an old, non-HD TV to hook up, borrow one from a friend and see if it doesn't work right. I bet it does - ergo, it's the TV. But you may not need a new one. Contact the manufacturer before lugging it back to the store.