'''''Hello bob,, i used to work on copiers back in the early 90,s.., you say that you cleaned the fuser brushes,, which led me to believe that, the unit in question has a fuser of some kind,, you need to get the fuser rollers out of the machine,, and clean or replace them.. over time with continued use the fuser rollers will get toner baked or embedded in them and no amount of cleaning will help.. if you can get the rollers out and clean them great,, but the rollers need to be slick and shiny and no damage to the surface of the rollers,, the rollers in the fuser unit impress the toner on the page,, even if you clean the rollers if they are damaged,,, they will pick up toner from your copies,, stick in the damaged area and start leaving streaks or smears again… i hope this help..joe'''''