Sonos told me via web chat that SMB and HTTP shares are no longer supported.

I do not have any form of share, but it still gives me the 913 error when trying to add the music library that is on my Mac. They told me to call the helpline but the wait time is over an hour. 

SONOS IS A DISGRACE to be honest. Terrible update, removing and breaking features. What a rubbish company.

agree did try to call them but would have to wait over an hour !

Same with me. Tried both options (connect to my music and connect via finder and marked the music folder).

Error 913

I’ve even tried the hard drive directly attached to the computer, still get the 913 error , 

All my music was from CDs and vinyl digitally put on to a hard drive, I don’t like subscriptions so mainly use my own music or the radio . All had been working fine up until this update. Please Sonos hurry up and fix this, or bring back the old app !

I just got off the phone with an Apple tech - he found this on reddit and it solved the problem also a video tutorial below

Go to sonosr/sonos•2 days ago

thedarkhalf47

Fix for Libraries on external drives or NAS on Mac (Error 913)

I could not access my music, which is sitting on an exteranl drive connected to a MacMini M2. Kept getting the Error 913. Here is a fix for that.

100% credit to the OP

https://en.community.sonos.com/controllers-and-music-services-229131/how-to-solve-the-error-913-music-library-on-a-mac-6894161?postid=16732714#post16732714

Video tutorial

https://www.youtube.com/watch?v=kjhKhDuvgDY

This worked for me after some screwing around. I still have lost access to my playlists but I can at least use the music files now.

I think, this is the original answer including the video he published.

It is an answer but it is not intuitive - never had to do this before. It’s basically a workaround, not a fix to the actual issue - the actual issue is Sonos force-releasing a piece of software that is not fit for purpose, rendering very expensive equipment half-useless. It is a disgrace.

But I am very grateful for this workaround. :)

Also BEWARE, if your iTunes/Music account changes password, the desktop app will simply disconnect your LOCAL music (??!!) but will just say not available. Music app itself will randomly disconnect from the speakers and say they are not available. It will not provide any meaningful notice but I discovered one must go onto an iPhone or Android and REAUTHORISE the Apple Music account. This is, once again, counter intuitive.

There in no excuse for this failure since the main function of SONOS from very begging was to connect local and NAS storages and play over the network (wired and wireless).  Now it’s just a third party service player.   How could they release a such an update is mind boggling.  I guess we should expect a fix and an apology. 

This is the best solution. Does not require you to move anything to a NAS because it makes your mac share the files over the network: