I too experienced a lot of white-flake problems when I was printing with my 9880.
Turned out, I had accumulated significant deposits of dust and flakes on the metal surface below the roll, and inside the plastic cover. When the printer would occasionally drive the media backward towards the roll, or when a roll of springy media would unwind on the spindle, the media surface would contact the crud.
When I started routinely cleaning those locations with a slightly moist towel, my dust problems disappeared. The 9880 does not have a motorized spindle, so back-driven paper simply expands loosely around the roll. I used my fingers to take up the media on the roll whenever the printer was driving backwards.
The flakes come off the roll at either end as the paper peels off the roll, then gradually work in towards the center by physics I do not fully understand.