I had an issue with the sound on one of my sets and called support and they had sent me a new modem for that particular TV. After connecting the new modem as I thought would solve the issue it did not. So this tv was about 10 yrs old and thought it was the set itself. I tried one more thing and found that unplugging the power to the TV would do it and sure enough it did. Just a thought when your having an issue with the sound try that.
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