Need Help with Strange Monitor Interference

[wrath]

Hello all! I'm new here and I'm trying to put a cab together.  Anyway, I just got a Viewsonic E220 21" monitor which I am hoping to use in my cab but something strange is happening with it. It looks like there is some kind of magnetic or other interference messing with the picture. It only shows up in the lower right hand corner and is about 3" long and an inch or so wide. It shows up as looking dirty on white backgrounds and darker / greenish on bright backgrounds like red. I call it magentic interference as it looks like what happens when you put a magnet near a monitor or unshielded speakers. I have moved the monitor all over my house and it looks perfect everywhere except where I have my cab. I can take it out of my cab and set it on the floor directly in front of it and it's still there. However, if I move it away from the cab and toward the other wall across the room it goes away. It's a small room, probably about 15' x 15' (if that), and I have an air hockey table down one side of the wall. At first I thought it might be that as the table is quite large but like I said, I can move it around the room and the discoloration goes away. I can also hold up a magnet in front of the screen and get rid of it that way too. I'm quite puzzled by this as there isn't anything magnetic in the room. I have no speakers near it at all. Any thoughts as to what might be causing this? Thanks.

[Ken Layton]

Power supply fan too close to the monitor? Power transformer too close? Fluorescent lamp ballast too close?

[wrath]

That's the strange thing, there is nothing else in the cab right now. No flourescent light, no speakers, and I can move the monitor away from that corner of my room and the problem goes away which tells me that it isn't an internal problem with the monitor. I am quite puzzled by what might be causing this interference. There is nothing magnetic in the room at all. I guess I can always move my cab to another corner in the room but it certainly seems weird that I can't have it in the corner I chose. Any other thoughts?

[DaveJ-UK]

There will always be magnetic fields wherever electronics are present.

Anything else plugged in behind or around the monitor?