yeah cheers will do i might have to try find the zip things that pull the headunit out of the pocket first, is a sony xplod, might see if ripco sell them or i guess ebay/tardme will have em, might check the earthing on the amp aswell he may not have scraped the paint back when he earthed it in the boot, or may have come loose since i moved the amp location
may end up getting someone to tidy it all up anyway and have a look at it, was a pretty jammy looking job by the previous owner of the car
My mate had the same problem in his B4 and we narrowed it down to cheap arse rca leads, changed them over with another set and hey presto the whine was gone!