04-16-2017, 05:32 PM
It sounds like you may have changed some settings over time as you imported new files. Perhaps at one point you turned off "Create subdirectory per song" and so the audio files were no longer placed inside folders. Are those mp3 files that are not assigned to any songs ones that were assigned to songs that you've deleted? Did you enable the "automatically import matching audio" option in the settings by chance?