Strange Mouse Problem, Please Help

Greetings,I just encountered a problem with my mouse in FS2002 last night. The mouse behaves strangely when you enter the sim after it loads. It acts normal when navigating the setup menus, aircraft selection, airport selection, etc.. As soon as the scenery loads and you enter the sim, the mouse responds very slowly to your commands and sways like you have very little control.I tried swapping the mouse with my old one and had the same problem, so I doubt it's the mouse itself. All my other programs work fine with the mouse. I looked under settings and it appears to OK. The mouse is one of the Logitech roller ball type. I've used it for a long time and never had a problem with it. The old mouse that also doesn't work is a standard mouse.Any help would be deeply appreciated.2.4 GHZ Pentium 4768MB PC2700 DDR SDRAMATI Radeon 64MB DDR Video CardThank you,Hans Groenewold