Ever heard of the display on a CRT wobbling? It’s just barely doing it. Subtle to the point that my fiance doesn’t notice it but it bugs the hell out of me. It’s a 6 year old Viewsonic. It’s as if there’s a fan or other magnetic device nearby, but there’s not.
So is the monitor dying a slow death or do I need to stop drinking so much?
Lol was going to say it sounds like there is a fan next to it… dunno, it might be the refresh rate if you have it set as the same as your lights in the room, try changing that maybe
all CRT’s do it to an extent. try changing the refresh rate to more then 60 Hz 
^ werd… try setting the refresh rate to 72 or 75 Hz
On some of my old CRT’s I used to own, higher refresh rates would do it aswell even though they supported crazy high refresh rates (heavy duty 21-22" CAD monitors) . it all comes down the the resolution you’re running on it too. Mess with it and find a happy medium
Your monitor has the pixel AIDS, burn it before your eyes shrivel up and die.
Otherwise:
-Refresh rate/Resolution
-Lighting
-Test on other video card/computer
-Monitor really does have AIDS.
It may be due to the quality of the power in your house. Try a different outlet or using a line conditioner.
Some sort of glitch screwed with my desktop settings. By glitch I mean either a software problem or female screwing with stuff best left to the men.
Refresh rate was set too high.