I had a question about that. I am assuming it goes by FID, right?

Yes, it goes by FID, not by song title or artist. Otherwise, it'd de-dupe songs that were different but had the same title, or were different performances of the same song. This way, it only de-dupes if you really have the same exact file referenced in multiple places in the playlist.

Remember that it only de-dupes when shuffling, so that way you don't get the same song twice in the shuffle. Sequential play doesn't de-dupe.

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Tony Fabris