Sometimes my windows, both driver and passenger side, would go down without any action from me. I can put them up with buttons tough. It's not like loose mechanics or broken cable: the glass seems to be solid in place, no movement if pulled by hand. It's like some phantom signal from a shortened switch cable. Strange thing about it is that both windows would go down completely in a synchronous manner. If it's a faulty switch I would guess only one window would do it.