File Save As PDF converts Item Numbers to question marks randomly

Greetings,

The context is we are performing a File -> Save As within Solidworks for a Drawing to convert to a PDF. We are currently running Solidworks 2015 sp02

The problem, the resulting PDF has Question Marks in item bubbles instead of the item numbers. I have tried different scenarios and there seems to be no repeatable use case.

Does anyone have any ideas that I can try or perhaps a resolution? The issue is we are generating PDFs on the server side as well for automation and it is occurring there as well as for users manually building the PDFs.

Thanks in advance for your time.

SolidworksDrawings And Detailing