A possible cause may be that appropriate paper is not used or the fixing unit is dirty. Check the following.
Have you loaded paper that is smaller than the size of the print data?
Check to make sure that the paper size matches the size of the print data.
Have you cleaned the fixing unit?
When you print a halftone image such as a photograph on a small size piece of heavy paper, do streaks appear on the paper?
Change the setting for <Rdc. Tnr Flaking from Heavy Sml. Ppr>. Setting this item to <On> may solve the problem. <Adjust Image Quality>
NOTE
If you set to <On>, the printing speed will be slower.
