I have 3 tv's in my house. My main plasma in the living room gets sound on every channel EXCEPT channel 3. My bedroom tv and my plasma in the basement get channel 3 sound. What is heck is going wrong with the main tv? I use a Onkyo sound system with this tv.
If your watching HDTV form over the air.- move antenna (low signal strength)
If comming from cable box - see if cable box has a volume control, otherwise bad cable box.
1. Move input source from TV that works to Tv that doesn't / move TV to diff source.
2. some older TVs have an Input switch for ch.3/ch.4 - change