First, let me say I am so glad that I came across this forum. I have already learned alot from reading the posts. I thank all of you who take the time to help.
I read the post regarding ground loops and I don't think that's the problem I'm having.
I have a Sony 5.1 system.
The noise I hear is more of a "whine" (or high-pitched hum, I guess). It's only on the Video 1 & Video 2 audio inputs. Also, it doesn't happen right away. It starts about an hour after turning it on.
Any help on possible causes and fixes would be greatly appreciated.
Thanks.