Have you ever dusted when you clean the houseRegardless of static charge, this is probably a good idea. "stuff" collects on surfaces over time no matter what. Have you ever cleaned a glass picture frame after it's been hanging for 2-3 years. It will have a light film of haze on it. That haze will build up on the mylar diaphragms whether they are charged or not, and can't be doing the sound any favors. I live near L.A. with 50% humidity and moderate pollution.