Last week I noticed the stereo in my truck had a loud static "pop" when I ran over a small bump in the road.  Later it changed stations when I went around a corner.  It continued to act more and more freaky as the week went on.  It randomly ran to full volume or ran to no volume.  It even started turning itself on and off.  Finally it just quit working.  Not even the backlighting would come on.

I pulled the stereo to see if I could repair a simple shorted wire or something.  When I got the unit out I could hear something rattling around inside.  I turned the thing upside down and a penny fell out of the CD slot.  But there were still more rattling around in there.  I opened up the radio and removed two more pennies from the circuit board.  

Reinstalling the stereo confirmed my suspicion that the thing was toast.  I questioned a potential suspect for the penny insertion.  There is a certain amount of communication difficulty, but I'm confident I've identified the culprit and corrective action has been taken to ensure no repeated offenses of this nature.