Two reasons for booth noise I identified and solved:
1.
Noisy back parcel shelf (shelf 2 on the photo below)
Noise is best described as clicks/rattles when going over bumps.
Reason: design flaw (two plastic pieces - between shelf 2 and booth frame are in contact)
Solution: Open hatch and unmount only the shelf 2.
While hatch still opened place shelf 2 in the position it would take if it was normally mounted (as after shelf 1). Now if if you press shelf 2 - you will see that there is plastic part below it relies directly on plastick part of booth (close to handles that put back seats down). Buy soft silicone or rubber fenders and place them between these two plastic parts (i glued them on shelf 2 plastic) and problem is gone.
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2.
Vibrating sound from the booth.
Mostly appearing when car is driven on low RPM (1-1.5), which clearly came from resonance and transmission tunnel.
Reason: low quality plastic of back license plate holder (blame the dealer)
Solution: Replacing the frame for better quality or putting silicone fenders behind license plate fixed the issue.
Cheers