I got a call from someone who'd received a new monitor, complaining that the new LCD screen was fuzzy. We went over to take a look, but couldn't find anything wrong with the display. To be on the safe side we replaced the cheep data cable that came with the screen, with a well shielded cable.
The next week I got another call from her: "I think I need a new monitor. Last week the tech replaced my cable, and that made it better, but it only works when I'm wearing my glasses. I know it's not the glasses, because the other day I got a new pair, and it's the same thing. As soon as I take my glasses off, the screen is fuzzy. And Shelly across from me, doesn't even wear glasses, and the screen is always fuzzy for her. So if you could get that replaced I'd appreciate it"