Hi Paul,
Make sure the correct type of bonding gunge is used. About 4 years ago I had a 98 R S8 and its screen had been replaced by a non-Audi dealership. I could hear constant clicks and creaks from the dash area and eventually I got the screen replaced by Audi. This stopped all the noise which I think was caused either by the wrong bonding gunge (not flexible enough?), or by part of the screen touching the frame.
As soon as you get it replaced, go for a drive with the heat full on to cause some expansion, and then open up the windows to get the inside really cold. Any clicks or creaks and I would tell them to do it again...
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Jon