That's an interesting noise but unfortunately not the one I have. I keep my seals gummi pfledged. I think mine is in the roof mechanism on that side. Rattles like hell now the temperatures are going back up. Out of warranty so time to play with adjustments and see what impact that has. At least if I have a go I can tell everyone what to try if I fix it... I could do with one of those car shaking machines you see on TV to help find rattles/squeaks...
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