madfast,
It is probably one of two things:
1. Window rials need to be greased.
2. Window rails out of adjustment.
If the window lands in the proper position when up (that is no wind noise and squarely seated on the rubber molding) it is probably #1.
If your car is a 1991-92 you really should check it you have the original window regulators and do the update and grease them. When the window starts to go slow, due to lack of grease, you really put a lot of pressure on the cable, which leads you to the imfamous broken regulator.
If you catch this early it is a $15 fix with the "Dali Window Fix-It Thingies". If you do not take care of it, it is a few hundred bucks PER SIDE!!!!!!!!!!!!!!!!!!!!!!!!!
HTH,
LarryB