A2000 Mouse problem

[TjLaZer]

The mouse on my A2000 only moves vertically up & down. I've tried several other amiga mice, but it's still the same problem. Replaced the CIA chips, checked everything over several times and have about given up.  It did work momentarily on the boot menu screen after trying a couple different keyboard commands.  I think I may have placed the mouse into joystick mode (somehow), but have no idea if that's the problem or how I could return it to normal mode.

Check this out:

http://www.rabayjr.com/Amiga/Flyer_Faq/toaster/mousdead.html