Letters in this font print as ⛝ on some printers

I am tentatively opening an issue here, please advice if appropriate.

I am experiencing an issue where some PDF documents (mainly produced with LibreOffice, I think) that use Source Sans 3 end up not printing correctly on some printers (many HP Laserjets show the issue). Specifically, when printing some characters (including common ones, like alphabetic chars, such as an "S") these get substituted by a square with a cross in it in the printout (⛝). The PDF is generated so that it embeds the font.

There are a few interesting things about this:
- The PDF document that does not print well will invariably display well using PDF viewers such as Okular, etc.
- Passing the PDF document through `ps2pdf` (a ghostscript based utility meant to convert PS documents into PDF ones, that can also take PDF inputs) results in a PDF that prints fine on that same printer.

This could be either
- a bug with the printer (maybe shared among different models and brands);
- a bug in the software chain used to generate the PDF (which I think always involves LibreOffice on linux and its PDF export function);
- a bug with the font

... but for sure there is something in this specific font *triggering* the problem, and I think that it would be great to identify it.

If some font expert could have the competence of looking in a PDF document showing the issue or to guide me in doing so, I can try synthesizing a reproducible case that I can share.