Audio hum/buzz with new surround sound setup

[suplexx]

I just bought a surround sound system because my tv's speakers are going and they sound awful. After hooking them up, I get an outrageous hum. I've been trying to get rid of it, but I can't figure it out. The problem seems to be the connection from the system to the TV.
Things I have tried:
-Different audio cables (no difference)
-Unplugging everything from the TV and power outlet.
-Making sure the box was a good distance from the TV
Also for some reason, if I take the cable, and touch the tip to the outer casing of the audio port, the humming completely goes away. Obviously this would mean I would only get mono sound, but I thought this might be helpful in diagnosing what's actually going on. Also lowering the BASS level helps some. The TV is a 37'' LG (37lg30). The surround system is the iLive HT050B. Thanks for any help.

 

[suplexx]

want to add that I have purchased a ground loop isolator and am using that as a temporary fix..the result is really quiet audio but not much of a buzz. still looking for solutions on this problem

 

[ssddx]

sounds to me like you may have a ground loop problem.

have you tried plugging the home theater system in to a different power outlet than the one your tv and other equipment uses?

have you tested the home theater set with a different input device already to verify that its not originating with the tv?

 

[suplexx]

Going to try plugging into a different outlet, and a seperate TV. Thanks for the ideas. I will report my findings

 

[suplexx]

Tried plugging in a different outlet, buzz is still there. Tried with a seperate tv and again the buzz remains. Hmm.