well dont check that menu.
1st of all...how you connected to your equiptment..if via Scart check that there aint any power cable running along side it?
2nd if its a cheap scart cable (ie supplied with tv,dvd, telewest box) then the shielding on that isnt all that great I would look into getting better cables that are shielded, and I know belkin networking gets slated but Scart cables are really good just look for the Pure AV brand, it does cost a couple of squids but well worth quality.
www.pureav.com/uk is the link./