steve - 9:31 am on Apr 8, 2005 (gmt 0)

Is the monitor signal lead the same?

What I'm trying to get at is it hardwired into the monitor or detachable? Could it be damaged?

Is it possible something else in the room or area is causing interference? Does the fault occur when the fridge, air conditioner, or arc welder your next door neighbour just bought turn on?

Try moving to another room, keep all your cables phsically seperated. Does this help?

How hot is your room, if its much hotter than the shop is overheating a possibility?