The WWWBoard Administrator responded with the following message.

Don, I would like to see a small crop, roughly 300x400 pixels, high quality JPEG, of one of the offending scans. It could be actual grain. I looked at some images a while ago (also from the UK) where the grain was much more obvious than camera shop prints-- because the image was much sharper. Radio Shack here in the USA has several line filters combined with surge protectors. I don't know how effective they would be; I've never had a problem (yes, I have some filtration on my mains; nothing fancy). I can't help in the UK.