USB devices cause computer to restart

[Midget]

Just rolled out some new images and found that now whenever you plug in any USB device the PC restarts. I have never seen anything as wierd as this before, and its extra wierd because its not limited to a certain motherboard and it worked fine before. The only thing that has changed is the image.

 

Does anyone have any idea what would be causing this so that I can fix it in the new image?