The handling of Unicode file names is not correct. When during a scan, the frontend encounters a file name containing accented characters like á or é, the scan stops and you have to abort the scan manually. On command line mode, you get a message like “Cannot open input file "Koite, Habib & Bamada - Wassiye.mp3" or it is empty”.
To recreate the problem simply name a file like:
Jussara Silveira - Lá Vem a Baina.mp3
Koité, Habib & Bamada - Wassiye.mp3