Brother DPC-8060 Service Manual page 367

(I-24) Toner specks
(1) Check the paper used meets the recommended paper specifications. A
(2) The toner cartridge may be damaged. Install a new toner cartridge.
(3) The drum unit may be damaged, or may be nearly at the end of life.
User Check
rough surfaced paper may cause the problem.
Install a new drum unit.
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