I have FINALLY solved the mystery of the degree symbol! Yea!! 
It’s MS. In their infinite wisdom - unlike the rest of the world - they expect unicode utf-16 to be the default unless you specify the source files to be utf-8. So when you use a unicode char like the degree symbol, which is takes 2 bytes in utf-16 (°) - with utf-8 it treats the string as 2 seperate bytes… thus you get the A°. There’s several work arounds, but since we’re not using a lot of unicode chars there’s an easy way around it… without messing up compiling with GCC.
If anyone notices any places where the apps are showing 2 chars instead of one, let me know, and I can fix the text string.