I noticed yesterday that a playlist that previously had over a hundred songs only had about a dozen. I thought I must have accidentally deleted or moved them somehow, so I began re-populating the playlist, and after putting a few songs back, suddenly noticed that the playlist was back to normal - it had over a hundred songs again.
I shut down my laptop, then when I checked again this morning, the playist was back down to a dozen songs.
Has anybody else experienced this 'feature' of Spotify?
Ok, I'm an idiot. Turns out that I had two playlists with the same name! I didn't even know that was possible. So one of the playlists had only about a dozen tracks, and the other had all of the tracks. Doh!