Question - Adding Media Types? #79

I want to play m4b files (audiobooks). These are just mp4's with the m4b extension.

Using MfPlayer I if I open a .m4b causes an error with the message 'An error has occurred (hr: -1072875836)'

Of course, if I rename the file to an a .mp4 everything works a treat (but I don't wanna re-name the file every time someone opens it of course)

So - I basically wanna add a media-type audio/mp4 for m4b (or force file.xyz to use audio/mp4 for example)

Possibly I need to use a different example / component to handle this?