These little flying bugs have been coming to our home annually for the last 5 years. They are approximately 3/16 ", gray to light black. If you touch them, a powdery substance comes off. They do not have a hard shell. They tend to congregate in our upper windows and leave when it gets dark. There are approximately 50 to 100 up on the window and some will go to other windows or lights in the house, but not in mass numbers. They appear to go under the trim on the window. They leave a mess on the windows. Eventually they seem to disappear after several weeks. What are they and how do we control them? Please note we do have potted live plants in this area. Spider plants and a jade plant. HELP! How do we control these little annoying creatures.