Music Playlist can’t find next item to play

Hi you all,

Suffering a problem with music playback.

Normally when you start a song in an album, it plays the next song automatically (yes, the setting is enabled).
But not any more. You see KODI going over the files, but it fails to play any of the remaining songs.
When I manually click on the next song and the next and… it sometimes plays fine (like in this log file),
but sometimes KODI won’t play anything anymore after the first song (can’t seem to reproduce this today, so no log) and I get the error ‘Item failed to play’.

Already tried to clean and update the music library (in order to get all the links right)

Any help is welcome. Hardware specs in my signature.
All my files are on a WD Live NAS device.

http://pastebin.com/9KRn7H4B