SonoSaver

SonoSaver lets you backup and restore your precious Sonos playlists. Multiple backups can be stored in a file and when backing-up/restoring, you have full control on what you would like to process. Or you can export them to various file formats such as CSV, M3U, Extended M3U, PLS, WPL (Windows Media Player playlist) and several XML variants with lots of options. In combination with iTunesPlaylistExporter you can even export them to Spotify. Search the store for "iTunesPlaylistExporter" for more infos about that.

TRY BEFORE YOU BUY: have a look at the trial version here: https://www.microsoft.com/en-us/p/sonosaver-trial/9mz90d8ccfgw (search the store for "SonoSaver Trial") Of you own the trial version, you'll get a discount when buying the full version.