1. PROBLEM STATEMENT: I am getting black (dark grey) streaks (Photo attached) from my prints, both prints from file and photocopies.

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PROBLEM: Black streaks on prints

2. ACTION TAKEN: I performed 'printer service > cleaning page'  multiple times but issue still persists.

3. OBESERVATION: Upon inspection, black (dark grey) streaks are observed on the following parts: (Photos attached) "Note: Terminologies used may be inaccurate, please refer to the image attached"

3(a) Imaging drum

3(b) Transfer roller

3(c) Transfer belt

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3(a) Streaks/tracks on 'Imaging Drum'

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3(b )(c) Streaks/tracks on 'Iransfer Belt' and 'Transfer Roller'

QUESTION:

Q1. What could be the cause of the problem above?

Q2. Can the hardware be cleaned? If so, what are the appropriate steps to do so?