tlmurray23 It appears from the FAQs that Express Dictate, but not Express Scribe, supports the m4a format on the Macintosh. This question is perhaps beyond the scope of this forum, but ... why? Were Scribe and Dictate originally created by different teams?
nchtj we'll certainly take a look at this one, i'm not sure myself what the differences are between them in terms of formats supported (because i did not development either of those products and i do not do any Mac development).