Brother tn 660 Toner showing horizontal white lines
- Paper (not rough or thick paper)
- Correct paper size & type
- Printer inside is dirty
- Damaged drum unit
Please try the following instruction:
- Print a few paper pages see if the problem will go away,
especially when the printer has not been used for a long time.
- Test with your old cartridge to see if the problem still occurs
- Check if you are using the appropriate paper and selected the correct paper size & type.