I have a 2016 Bennington S21 and the vinyl floor on the stern only, has dark orange spots all over it I think it must be from the sun as that is the only part that does not get covered from the boat cover, I have tried power washing it but it wont phase it, its looks terrible. has any one had this problem? is it defective flooring? I took it back to the dealer but all they told me was all they could do is power wash it. I did that dose not help. any suggestions?