This next picture shows a close-up of the problem area. Note the round bar that runs down this channel. This bar controls the movement of the wind deflector. So it moves forward and backward down this channel. The reason I believe that some people are having this rattling problem and others are not is due to the fact that if the sunroof is not adjusted just perfectly, than this bar has some load on it, which causes it to flex slightly bringing it closer to the channel edge.

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