I obtained about a year ago a pair of Audio-Technica ATH-A500s off craigslist for 10 bucks, which was a steal.
The guy thought that the thing was broken, and so wanted to get rid of it for some money. I got it, then looked to see if it really was broken. After some further inspection, I saw that the gold connecting piece had broken, with a bend in it and some connection issues on the inside. I went to a nearby radioshack and bought a new connector piece, and now these headphones work like new.
I LOVe these headphones, they sound incredible, though they do feel kind of flimsy.