What caused this shortage in a PS2?

I wanted to know if anyone has had this problem with their PS2. I was at my friends house today and we were watching some movies on her PS2. While we were watching the movies it went spastic. It paused, stopped, went in rewind, fast forwarded, pushed all the ons, played and tried to get the code back in. Then it would stop and happened again an hour after the first and 20 min after the second time. Then when we play a video game and pause, it would un pause and the person would walk, fight, and do random things. Its like the controller had a mind of its own. Anyone know what thing in a PS2 causes that?