Texas . . .
Sometimes it's the font itself (doesn't support those characters) but, I've found mostly it's still WORD ... by turning off Smart Tags and AutoCorrect items. Of course this turns off Words auto-functionality, if that bothers you.
Mine all cleared up when made sure, under AutoCorrect, AutoFormat Tab, Replace, all boxes were un-checked except Internet and network paths with hyperlinks. And . . .
I don't use Smart Tags, I unchecked Everything under AutoCorrect tab except Replace text as you type, and Under the AutoFormat As You Type Tag --- everything is unchecked!
And finally, the garbage went away in PiP postings.
Hope the above makes sense...if not, it's Word's fault, not mine!! (lol)