I ran into this problem as well. It seems that the filesystem paths should not contain non-ASCII characters. In my case, my music is stored in ~/Música and scan.py fails on every single audio file it finds.

> ProgrammingError: (ProgrammingError) You must not use 8-bit bytestrings unless you use a text_factory that can interpret 8-bit bytestrings (like text_factory = str). It is highly recommended that you instead just switch your application to Unicode strings. u'SELECT songs.filename AS songs_filename, songs.id AS songs_id, songs.title AS songs_title, songs.album AS songs_album, songs.artist AS songs_artist, songs.mimetype AS songs_mimetype, songs.year AS songs_year, songs.track AS songs_track, songs.disc AS songs_disc, songs.lastmodified AS songs_lastmodified, songs.filesize AS songs_filesize, songs.length AS songs_length \nFROM songs \nWHERE songs.filename = ?' ('/home/dschulz/M\xc3\xbasica/Michel_Petrucciani/Blue_Note/06-Trouble.mp3',)