Symbology issue when exporting to PDF or TIFF

[AdamInglis]

I'm using provincial highway shields in ArcMap without an issue, but when I export the map to PDF or TIFF some of the symbols get a shuttered effect and appear semi transparent when printed (see below)

Any suggestions on how to fix this?  I have played with all of the PDF export settings with no luck.  I'm starting to think it might be a problem with the file format my Mark Text Background is in, but before I go down that rabbit hole I thought I'd give the community a chance to chime in.

Cheers,

Adam

[KishorGhatage]

I know this is different however see if it could give you any idea to play with symbology.

Hatch distortion

Kishor

[BenGrod]

Adam, you probably tried this already but just in case did you select "Embed All Document Fonts" in the PDF options?