unplug everything USB, one of your USB devices are not supoorted by knoppix (or is broken) my guess is a USB keyboard or mouse, poissibly a USB wireless device or disk
EDIT
did a search and according to that is looks like a keyboard.
endor=0a81 ProdID=0103 Rev= 1.10
S: Manufacturer=+
S: Product=USB Keyboard
/EDIT

I have had something not quite like this his happen to me once, that time it was a broken USB controller on the motherboard.