I have the same problem, but I think it's driverrelated and not tv-related, because when I use the drivers on the CD that came with the motherboard it works perfectly, but with the 8.10 drivers from AMD or the latest drivers from motherboard producer it doesn't. I loose the sound if I change the input on the tv from HDMI1 to anything else and back, or if I turn off the TV. I get it back if I logg out and in, or if I hibernate and wake up, so I guess it reconnects when drivers are "reloaded".
This is not on the Gigabyte board, but Asus M3A-H/HDMI. And I don't think I had the problem pre-8.10 either.
I have not tested the 8.11 drivers yet, because of other people reporting other problems with it, but hopefully it's fixed by now and will be working in 8.12.
Edit:
Ok, since I'm reinstalling my computer in the next few days I decided to try 8.11, and it does work for me now.
This is not on the Gigabyte board, but Asus M3A-H/HDMI. And I don't think I had the problem pre-8.10 either.
I have not tested the 8.11 drivers yet, because of other people reporting other problems with it, but hopefully it's fixed by now and will be working in 8.12.
Edit:
Ok, since I'm reinstalling my computer in the next few days I decided to try 8.11, and it does work for me now.