How did you create the PDF files? Adobe Reader can't create PDF files.
i'm always creating them first with microsoft word 2008 for mac 12.3.3 as WORD DOCUMENTS (.docx) which is currently updated - then saving them (converting them) as PDF's
Check the conversion settings of MS Word.
searching MS WORD > HELP > CONVERSION SETTINGS
doesn't give me anything close to this issue
any idea where to find those conversion settings ?