This issue for me has been resolved. Here is the fix. I have a 2019 GT1.
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Pushing up around the edge of the headliner all around the
sunroof glass. I used the palm of my hand and gave a solid push all the way around. In two spots I felt and heard a "click".... you could feel the Velcro strips connecting better. Drove the car and now it is quite...not a
single creek from up top. This is definitely the issue since I could reproduce the noise every day during normal driving. It has been a few days now and the noise is completely gone. I did let the dealership know what the fix is for future reference for others.
Had the car at two dealerships and neither could fix issue. They tighten all the
bolts on the rails... grease the rails and told me they could not fix issue without ripping apart sunroof. I called them today and told them the fix for their records.
All that said, for all those that are hearing a plastic type crinkle sound from above your head.... not a rattle of metal.... and if you open
sun shade or glass or tilt glass and non of that makes the sound go away....then most likely your fix is a 30 second push of the headliner where it meets the opening (all around) listening and feeling for a "click" sound is all all you need to do.