Yeah, that was me. And it wasn't against the vent holes... it was just the bare metal in the case that's rough enough to wear away the plastic on the wires.

Do a quick inspection of your drive cable and make sure there aren't any worn away points where there is bare wire exposed. My unit showed the same symptoms, and some electrical tape over the worn wires fixed it up. I still have to stick the new drive cable David sent me in there... but it works for now so i haven't bothered.