Our copies are streaky like the drum is not clean.... help! There is black streaks on the top of all of our copies on our canon imagerunner 3300.

Horizontal streaks are usually the toner cartridge or the drum; vertical steaks are usually the thermostat or the fuser.

If you are getting horizontal streaks and changing the toner cartridge out fixes the issue temporarily, I suspect you probably have people taking the blank pages that print out after printing and feeding them back through the printer to save paper. The old paper picks up a charge when fed through the first time, pulls toner up the second like a magnet, and deposits the toner onto the toner drum. When the next sheet comes through, the image itself or a black line of toner can be pulled from the last sheet (or the sheet before) and is transferred over the new image. Change your toner and print several pages to the printer, see if the problem fades and goes away.

If it does, just tell people to either stop feeding the blank pages through, or to at least turn them over and put them at the bottom of the paper stack. This will give it time to dissipate the charge before feeding back through.

A) Black Streaks, Shadows, And Ghosting
Adjust the printer's lightness/darkness setting to 2-3 different variables and see if problem disappears. Look at the fusing assembly - is the roller torn or does it have any black buildup? Use caution!!! It gets HOT!

Try another toner also.