If you have a Samsung LCD TV and an Apple TV connected to it, it's possible you'll occasionally lose the HDMI signal from the Apple TV -- in particular when you turn off/on the TV. I corrected this problem on my set as follows (thanks to Marco in Apple's Discussion Forum for the help). Note that you'll have to access the Service Menu on your TV.
IMPORTANT: Be careful! This Menu has very important parameters which you should not change at all. You could 'brick' your TV if you change the wrong parameter!
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