have noise on my plasma

when watching tv i notice horizontal bars moving from top to bottom on the screen. this does not show up when viewing dvd's.is it rf noise through the cable? any suggestions to cure this?
You can take a long line straight from your cable tap or ground block to your plasma and then you will know if its your IW or its your signal coming in. If you find its the signal coming in you just call the cable company and complain like theres no tomorrow and maybe in a month or so they'll finally fix it for you. If you find its your IW then you might need to either replace the connectors or splitter or the whole line. Hope this helps.