[citricsquid]

You're missing the point!

They don't need to filter the audio files themselves, that's completely un-needed, all they need to do is filter the meta data (eg: artist name, song title, album name). That is not hard. If you have a list of artists with their songs and albums you could easily match the submitted data against this and work out if the submission is disallowed. If they upload with "fake" meta data (eg: fake artist name) it doesn't matter because no user is going to find that music.