Interference on Plasma TV

[CDC]

I've got one for you pros out there. Sorry about the legnth.
In Nov. 06, we installed a 50 some inch Plasma tv for a client on the opposite wall from his equipment. The power for the eq. is from a sub-panel in the addition where the HT is located. The circuit that feeds the tv is from a sub-panel in the older part of the home. The whole service was redone in the last 10 years, and all wiring appears to be correct. The component video signal is on cat5e cable with video baluns (approx 90 foot run). After installation, there were very distinct horiz. lines on the display. However, when we plugged the tv into other circuits (even from the same panel) the lines would disappear and the picture was great. We decided there was a ground loop problem on that phase of the service and isolated the ground from the circuit at the connection to the tv. This seemed to have cleared the problem. Now the client has called to say there is still interference on the tv. The access is very limited and all other circuits in the attic space seem to be switched (lighting). I am wondering if a power conditioner is what I need. Any help would be appriciated.

CDC

 

[CollinR]

After installation, there were very distinct horiz. lines on the display. However, when we plugged the tv into other circuits (even from the same panel) the lines would disappear and the picture was great. We decided there was a ground loop problem on that phase of the service and isolated the ground from the circuit at the connection to the tv. This seemed to have cleared the problem. Now the client has called to say there is still interference on the tv.

Were the lines scrolling vertically or static?

 

[CDC]

The lines are scrolling. I have ordered a power conditioner from Furman. I figure, even if I don't use it there I'll use it on my own system. It looks like good stuff. Thanks for any help.