jeana1980,
It sounds like an issue with the HDCP technology inside of the cable/sat box. Often times, when the screen goes out, yet the sound stays on, that indicates that the box thinks it may not be hooked up to a panel. This technology is to eliminate the ability to stream the signal to a computer or non-panel device.
Often times, turning off the cable box and letting the HDCP reconnect automatically will do the trick.
--HDTech
My tv works fine for about 2 hours and then the screen goes blank but the sound stays on. After shutting the tv off, and letting it set for a few minutes, it then works fine for about a half an hour. It does the same thing when playing the wii so we assume it is unrelated to the cable box. Can you help??

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