A few of you may remember I was plagued with herringbone interference on the capture side of my HTPC. Tried many things: new RGB to svideo convertor , new mains leads , RA filter contraptions , 4 different capture cards (including a falcon). Interference varied but never really went away entirely. Just replaced the 5m svideo lead (lektropacks) with a new one (Ixos) ....no more herringbone. The intermittent nature of the interference and the supposedly good quality of the lektropacks cable dissuaded me from assuming the cable was the culpret. Just goes to show never assume anything.