HAVING ERROR PROBLEM. It says It can't add assets

Dear Stephan

Can you attach the FCPXML and the full text of the error message, so we can see which clip this is and where in your timeline.

Yours sincerely

James

I'm getting this message from X2pro.

An error occurred converting final cut xml to aaf
adding assets to aaf file
adding essence for asset {it lists a certain sound file} that's not even used in this project.
opening audio extractor for portion 0 of asset {lists the same sound file}
failed to initialise audio extractor with default bit depth of 16
error setting up for audio extraction (the requested URS was not found on this server)

then it says suggestion : Does this movie contain an unsupported audio format?
and it doesn't.

I'm confused. I'm sure it has something to do with a weird way I imported one of those files on final cut. The file is not even used on the project.