The download that I got had .mp3 and .oog files for the music. Many dont have the .oog, so I ignored it.
Bad choice. made two instances of each song in the media library.
Deleted all the tracks from the Media Library ( left click on any track in library >CRTL+A > right click > delete songs from database > YES to remove selected.... ) Then a pause while it does so. THEN it asks if you want to delete form the disk.
IF they are junk, YES. IF you just have to edit and try again, NO.
I f'd up and said yes the first time, when I just had to edit. Re-downloaded the folder.... D'oH!!!
So I went to the folder, organized by file type, and deleted all the .oog files. Imported the folder again, and YES!!! No dupes.
Hope this saves someone some frustration.