Word to pdf produces tints behind text

This question really has absolutely nothing to do with type and typography. It is really a question of Creating PDFs. As such, I am moving this thread to the appropriate forum.

Without further information, it is virtually impossible to answer your question. For example, what version of Word is being used on what platform (i.e., Windows, MacOS)? How exactly is the PDF file being produced? Microsoft's own PDF creation? Adobe Acrobat PDF creation? What settings options are being used to create the PDF file? What “color” is the text? “Black” text? You and your customer should be aware that “black” or “gray” in Microsoft applications is really RGB black or gray (R=G=B) and depending upon how you create the PDF file or process it afterwards, what you think is black or gray may be rendered with other inks as well (for printing).

You might also want to post (on some server we can access) a sample of the offending PDF files for us to analyze.

          - Dov