Default [Q] Music not shown on the default music player

I copied some music on the phone, I can see the folder and every song if I search them in ES File Explorer, and even play them with the built-in music player in ES, but I can't play any music with the default music player, it says that there's no files.
The default file browser also can't see the music, more specifically if I look for it in the "all files" I can find it and even play the music, but in the music section of the file browser it says that there's 0 file, here's a screenshot: http://i.imgur.com/CNCnQD9.png (it's not in English, but I think it's pretty straight-forward which one is the music).

How could I fix this?