Whistling vent window making me crazy!

[RShaips]

I have completely restored my truck, all new interior,carpet and insulation on the floor. Both of my vent windows are brand new, and the drivers side makes all kind of noise. I have done everything possible to seal it better with no luck. Finally I installed a different used vent window and guess what happened...the other vent window started to leak! I have come to the conclusion that it is not the windows fault. I am going to put the new one back in. Why is this happening I am ready to give up.Any suggestions?