My parents recently purchased the LG 55LS4500 from BestBuy. A couple of days after delivery, the screen suddenly DIMMED while my dad was watching it. He turned it off, turned it back on, and it was fine. But a couple of hours later, the screen dimmed again. He contacted BestBuy and they promptly delivered a new TV (surprisingly good service, by the way).
Guess what? The exact same thing happened on the new TV. The screen dimmed again, only this time it happened within a few hours of watching TV.
The problem is similar to a screen saver type of thing... only there's no screen saver setting on this TV.
Anyone have any thoughts as to why this might be happening?