So, the external SSD is not set up as an NAS? Just a mapped drive in the Mac OS? Assuming the external SSD is ‘on’ and reachable by the Mac’s OS, the Sonos client should be able to see it. Of course, we’re making all sorts of assumptions about which MacOS you’re using, and which Sonos client you have installed on the Mac, and what device you’re using as a controller.

I’d be tempted to submit a system diagnostic, and call Sonos Support to discuss it.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

It’s important to note, however, that it isn’t the Sonos controller/device it is running on that is playing the music, the ‘player’ is on the Sonos speaker, and it is the thing reaching across your network to reach this data. 

What an odd response.

1) and 2) don’t apply here at all. And I’m unsure of what library app is being talked about in 3), 4) and 5). But 6)  makes sense, as it echoes something I’ve already suggested.

If I were to guess, this is a chat bot generated response. 

Moderator edit: AI-generated post to which this is a response has been trashed.

 Thanks Bruce. To clarify: Yes, the external SSD is NOT set up as a NAS. It’s just connected to the Mac via USB and is being mapped by the OS. I’m running macOS 14.4.1 on an M2 Pro Mac Mini. The app is Sonos Controller for Mac version 16.1. 

Ok. I’ve spoken to Sonos and I now have the answer. It’s really weird but it turns out that it related to the format of the drive your music is on. If it’s on the internal storage of a Mac, then it can deal with APFS fine but if you have your music on an external drive connected to your Mac then it has to be either  Mac OS Extended (Journaled) or HFS+. So if you have your music on an external drive then that drive has to be using a legacy format but if it’s on the internal storage then the current format is fine. 

Interesting, I was unaware of this. Thanks for posting the data here!

No problem. I’ve seen quite a few posts about this but none that have got a definitive answer so I hope this helps others. 

Does anyone have a solution for this? @Sonos, I haven’t had my library since the new app, and keep getting turned back when Sonos asks for my password and tries to access the file share.  My last successful setup was done with the old app.  Desparately hoping this will work from the app again soon.