key fob randomly activates door locks
 

Over the past year the key fob has started to lock the doors even when I haven't pushed the lock button on the fob. I've even tested it by leaving the keys on the dash so I know nothing has touched the button - and it will just activate and lock the doors. Today it went off by itself while the key was in the ignition and the car was at a parking garage. $180 to have a locksmith get the car unlocked. What's going on? This is on a 2002 Golf. :confused: