This is a brand new printer (Laser Jet Pro M255dw) and I had this problem so I exchanged for a replacement and I have the exact same issue. The issue at hand: when printing from a Word Document, colors are true, but when printing from a PDF document, the color blue IS NOT a true blue color-- it resembles closely to the true purple color. Cyan is not printing true color from PDF. I tried several different PDF files to make sure the one printing from was not corrupted. The issue is definitely the printer and not the file.
Thanks in advance for any help regarding this issue,
Try printing from a different PDF program such as Foxit, you can also try different drivers to see if the results are different. There are also numerous settings in the driver as to which color profile is used.
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