When Spotify users disputed the randomness of the music streaming service's shuffling, the company rethought its algorithm.
Users sometimes heard multiple songs by the same artist one right after the other, and from this surmised that Spotify was not randomly ordering their playlists. To address user concerns, Spotify switched from the Fisher-Yates shuffle they had been using to an algorithm inspired by Floyd-Steinberg dithering.
Graphics in a Spotify Labs post help illustrate how the revised process works. Read the post.