l have been using the 303 protectant on the rubber for a long time. I put it on all the rubber on my current vehicle and after I wash it the rubber looks terrible. It looks very dull on most of the rubber but on some it is like before I washed the car, so that part looks shiney. What do you think is going on here? Are there any recommendations you can make for my using the 303 or another product that will work. Thank You!