I'm having trouble with my HP OfficeJet 6500 all-in-one. I'm out of warranty, so there's little help from HP...
When I scan or copy something, using either the flatbed or the ADF, I get horizontal black lines randomly across the document. I've got the latest drivers and the latest updates.
I know it isn't a dirt issue on the screen -- the lines are in different places...sometimes it's just a few at the bottom, sometimes it is all over the screen.
I thought it might be a PC issue -- but it happens in standalone copy mode, too.
Here are a couple of examples...
Really bad example: