I have a problem with white vinyl siding. The front of the house is covered with tiny brown/black spots about 1 to 2mm in diameter.These spots are three dimentional, raising about 1mm from the surface. One person says they're egg casings from an insect, another says that they're fungus spores. Either way, I'm having a hard time removing them. TSP and Clorox as well as a Power washer have been used. I've tried using bug and tar remover for a car, nothing seems to work. Anyone have a suggestion?