As I mentioned above, I have a persistent problem with one window which will one-touch up but not one-touch down. Since everything else works as it should (it's a convertible) I suspect it's a dodgy switch. If the switch is making an intermittent connection due to, say, dirt in the switch, it would appear to the car as if you were pressing and releasing the switch over and over (like a light flickering). I couldn't be bothered to investigate the issue on my car but if I did, I'd start by swapping over the switch connections between the right and left windows to see if the symptoms followed. Of course, I could be talking nonsense.