How to clean fly dirt from vinyl siding?

The front of my house faces east and gets the morning sun. Flies use the light grey siding and porch area to take advantage of the warm early morning sun. The siding and white vinyl porch rails, and grey vinyl chairs are covered with tiny black specs of fly poop. I think we have tried every type of super cleaner known to man including those Mr. Clean sponge type things and kerosine. All I have succeeded in doing is dulling the finish where I have tried to clean. The poop doesn't budge. Does anybody have a solution for this. I am sure I am not the only one with this cleaning problem as flies are everywhere.