96 Passat GLS windows rolling down in rain

[RJuntunen]

I have a 1996 Passat GLS that I recently bought. I learned today that the wondows decide to roll down when it rains ... wasn't to happy about that because then when I went to raise them the drivers side window fel into the door. I got the window back up when I got home but I need to know why the windows roll down when it rains. If anyone could provide any help it would be much appreciated. I am wondering if it could be something with the power mirror switch, it doesn't work but when I take the panel off it is all electrical taped together so could it be shorting out possibly and that be the reason of the windows falling?