Exporting AAF error....

Hi, guys. I'm trying to export an AAF from my sequence and am continually met with this error:

Cannot embed audio because "/Volumes/Capture Scratch....002/RAW/CONTENTS/CLIPS001/AA0033/AA003301.MXF" also contains video. Only audio-only media files can be embedded.

That is for each of the 50+ clips is have in the sequence.

Not sure what is wrong here. I'm working with all interview footage shot on a C300. I understand of course that the MXF file "contains video" but am I missing something with how to export the audio tracks only? I'm not sure why, when exporting the AAF, I'd have to specify that but would like to know how to do this or how you guys get around this. Is it a bug and you can only use OMFs?