Kirkinner,
while your rattle could be the issue you are discussing with others here, I also wonder if it could be your post-production strut. I suspect that is a fairly unusual add-on. I'm guessing you ordered your X w/o the space-saver spare and subsequently added the spare and the strut. I hope you will report back as you solve this issue. I am curious about the strut. I did not order with the spare and added one after delivery. I did not know the strut could be added so I never asked. How much did they charge you for that part and install? Do you think it is essential? While I got the spare hoping to never use it, I did not even know about the strut and just assumed that I could manage the spare out of storage compartment if needed. But, I have never tried to see just how far the storage lid will open (lean back to stay open?). I am the only one who drives my vehicle so I suspect, if I ever do need it, I could hold the cover open with one hand and lift out the spare with the other hand. But, you have tickled my curiosity about the strut. Thanks!