When I watch HD channels, my TV shuts itself off. Sometimes after 10 - 15 mins., sometimes even sooner.
Your TV shuts itself off just on the HD channels? Couple things that could be -
1. The TV isn't picking up a signal from the HD box.
2. The sleep timer is turned on in the TV's settings
If it's turning off while you're watching TV, it's unlikely of course to be the first option.
Take a look in the TV's settings and see if there is anything set to turn it off if there's no input from the remote control after a set amount of time. There should also be something in the TV's settings to reset it to default just in case.
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