Denim top discolours ! Help
 

My denim blue top on a MCS R57 has been replaced 2 weeks ago after white rub spots appeared after not even 500 mls. Now the second top also gets these rubspots. It looks like the mechanism folds the top too much or that the denim cloth is really like a jeans , fading colour quickly. My dealer suggests I have a 3rd top installed but now a brown or black one !! Anyone with a blue denim top out there ? Any similar experiences ?
Thanks as I really get enough of having been 13 times back to my dealer in 10 months for all sort of problems except regular maintenance !!