Hi,
I had some problems with the passenger window a couple of months ago, so took off the door card and had a good play with the whole mechanism. It is a 'door card off' job and you need to peel back the polythene layer behind the door card to get access to the window mechanism.
The window runners, at the front and back of the window inside the door, have adjustable stops fitted to them. It appears that you can loosen these stops and adjust them to move the window closed position up/down a little at each end.
I had a severe ‘clunking noise’ when opening/closing the window. After ages of playing with the mechanism and adjusting the stops, my problem turned out to be a missing nut, which attaches the window to the mechanism.
Hope this helps

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