Found it!
Well after a little experementation ive worked out how to fix this problem....
Here it is step by step....
1) Open up Fifa 06 demo, then minimise it (ALT+ TA
2) Press start and then go into the control pannel
3) go to performance and maintainance..... then system
4) a box should pop up, click on the hardware tab
5) open up the device manager
6) click the + next to "Human Interface Devices"
7) now its down to tiral and error keep on disableing things and swiching bettween fifa06 and the device manager, eventually you will disable the ting causing the problem. (just remember not to disable your keyboard and mouse)
for myself i disabled everything bar by usb keyboard and mouse and the demo worked perfectly......
p.s some of the steps in this guide may be different for others as ppl have different versions of xp and different menu set-ups bu aslong as you can get the device manager up you can work fro step
If you need any more info just ask!
I found this on Ea Forum!