iPod locking up my computer

I have a 20 gig iPod, and everytime I plug it into my iMac or unplug it, it freaks my computer out. I'm still able to move my cursor around, but I can't click on anything. If I make the finder quit, everything clears up and goes back to normal. I've run disk first aid and repaired minor problems, but it didn't seem to help. I've also had the same problem when my computer wakes up. The problem didn't start until after I got my iPod 6 months ago.

Any ideas?