I believe that there is a Sonos 10,000 track limit across ALL playlists, could that perhaps be the reason in this instance?

Why do you believe that there is a 10,000 track limite across ALL playlists?  Do  you have a source for that opinion?

If one song is in 50 playlists, is that one track or fifty tracks toward the total?

I’ve seen it mentioned in the past a few times on the forum - here is one example I found a few moments ago:

I’m not personally sure if it relates to individual tracks - but my thoughts are it perhaps relates to 10,000 entries across all playlists - but if you wish to check things further, then Sonos Support Staff can be contacted via this link:

https://support.sonos.com/s/contact

Here’s a further mention of the 10.000 limit…

Thanks for the info.

So we are only allowed to have 10,000 songs in our Sonos Playlists, and having the same song in more than one playlist counts as two songs?

I have about 29,000 mp3 files, so 29,000 songs altogether.  Some of my playlists are “songs played three times” and “songs played four times”, etc.  I do this so I can occassionally tell iTunes / Sonos to play the songs that have gotten less plays compared to the more popular tunes.  These “songs played XX times” playlists include all ~29,000 songs, so …. I guess that’s too many for Sonos?  I can remove those playlists, but I’d rather not.

Do you know if there is a way to tell Sonos to add specific playlists of my choosing to the Sonos system rather than have Sonos start at the top (playlists beginnning with the letter A) and work it’s way down until it gets full at 10,000 songs?  That would solve the problem - allowing me to choose which 10-20 playlists can be accessed at a given time, and then I can rotate the playlists in Sonos when I’m in the mood to do so. 

Can a user control which playlists are and are not imported into Sonos?

Maybe see this support link..

https://support.sonos.com/en-us/article/itunes-playlists-missing-from-sonos-library-on-usb-drive

The iTunes Music Library.xml file is a text file and so I guess you could spend some time editing a copy of that and use that in your library path. Another option is to ditch using the .xml file and export the playlists from it using an iOS App (MusicStreamer is one example that will do that) then save the playlists as individual .m3u playlists.

Here’s some more information you might find helpful…

I personally now find that straightforward UNC paths direct to each of the chosen local music library tracks, as a single ‘one-line’ entry, seems to work best for each .m3u playlist.

Here are a couple of ‘example’ entries (as seen in a text editor) to hopefully demonstrate what I mean, but clearly your own network path will be different:

\\192.168.0.1\MyNAS\MyLibraryShares\Music\Genesis\Trespass\The Knife.flac

\\192.168.0.1\MyNAS\MyLibraryShares\Music\Genesis\Trespass\Stagnation.flac

I also chose to strip out everything else from the playlist file, including these ‘directive extensions’…

• #EXTM3U - file header
• #EXTINF: - track information/title

Note: Some .m3u playlist files may contain other types of ‘extensions’, which can all be removed. See this link :

https://en.wikipedia.org/wiki/M3U

The extensions are not required for Sonos use, so I personally found removing ALL worked best for speed of loading the playlist.

In addition to the format stated above, the netbios name of the host NAS/PC also works well in place of the LAN IP address. Example:

\\MyWindowsPC\MyNAS\MyLibraryShares\Music\Genesis\Trespass\The Knife.flac

I have gone onto convert all my playlists to the above format and have just opted to place them in a separate folder within the local library, but they can be stored anywhere in the library that you’re indexing when using the UNC path for each track.

Using the above method I was able to get a 25,000+ playlist to load to a Sonos player queue in a matter of a few seconds, well within a 15 second timeout period, which is another limitation in the Sonos App

Anyhow, I hope that assists.