We are unable to reproduce this issue. This is good for other users, but it makes it harder for us to help you all here.

@Ken_Griffiths - I’m told you have a different issue than the others - no NAT Loopback will prevent Plex from working.

@pwt & @timmyc - Could you please let me know your current Plex server network settings? Thanks.

That page is well out of date. The latest downloads for S1 are 11.2.13.

Hi @Ken_Griffiths 

Fantastic! Glad to hear it! Thanks for updating the thread.

This was a separate issue that was resolved as far as I’m aware. There’s a thread on the Plex forum about it - seemed to be that Sonos’ Plex integration was passing a malformed request string to the Plex API which is now fixed. I’ve not seen this for a few weeks now. https://forums.plex.tv/t/unable-to-browse-music-using-sonos-with-pms-1-24-1-4931/740590

Quick update on this…

Spent over an hour on the phone with Sonos support, who basically went through same troubleshooting steps I had. Very thorough and helpful but unfortunately couldn’t identify any issues their end and suggested it might be a ‘Plex account issue’. (Not entirely sure what that means!)

Anyway, checked out the Plex logs again and there’s a couple of messages related to TLS:

CERT: incomplete TLS handshake from <my router IP> no shared cipher

Based on this, in Plex, I changed the TLS setting from ‘Preferred’ to ‘Disabled’, and boom, I can play music again!

There’s also an option in Plex ‘Strict TLS’ which forces only the most secure ciphers, etc. This seemed to have no effect.

I haven’t solved this fully, so need to investigate further, but my suspicion is that Sonos is using an older TLS cipher that’s been deprecated in the latest Plex version.

Will update again when I find out more.

Oh, one other issue - although I can now play music by disabling TLS (which I don’t want to do long term), the dreaded ‘Unable to browse music’ error has reappeared!

Addendum to my previous - I don’t actually have TLS set up on this setup, so not sure why my TLS was ‘preferred anyway’. Still, it’s another avenue to investigate when I get time.

A passing observation: Unless the Plume is in bridge mode you’ll be in double NAT, assuming there’s an ISP router. Forwarding inbound traffic therefore wouldn’t work, at least without jumping through some extra hoops.

I can do that, but not for some time, because I need to test using my remote Sonos S1 system, which is installed at a different property.

If I get time, I might flip my local S1 system onto a different network to the Plex server, and use that for testing.

I do appreciate you & your colleagues taking time to look into this.

Thank-you for looking into this issue @Corry P. that’s much appreciated. I will continue to press Plume to have the option to enable ‘Nat Loopback’ on their router. Plume have been canvassed about the issue previously and by others too, so I’ll see how that goes.

There are other ways to play the same music on Sonos, so it’s not a bother, other than perhaps the time spent trying to eventually get to the crux of the matter.

Hi @timmyc 

I’m glad to hear that the issue, for you at least, now seems to be resolved - thanks for sharing those details, and for updating us all here.

Is anyone still able to reproduce this issue after reboots and updates?

Hi @pwt 

Thanks for that. Yes, we tested a speaker on a mobile hotspot connecting via LTE to the Plex server. Our Plex settings match yours, and Strict TLS doesn’t appear to make any difference.

Are you running the native Plex server, or on a Docker Container?

It’s in a container, running with ‘--net=host’, so it should behave from a networking perspective as if it’s running directly on the host.

Hi @pwt

And we’re doing the same. We still can’t reproduce the issue - though it seems related to SSL. 

Hopefully, more information will come to light soon. Until then, being unable to reproduce, we’re unable to continue.

Thanks. Just to check: you’re testing using an S1 Sonos system?

If so, this is really odd. It used to work perfectly, but stopped doing so several months ago, despite no changes in networks or other relevant configuration settings -- other than normal software updates to Sonos and Plex.

I did wonder if it might be as simple as a certificate expiry, but if you’re not able to reproduce the issue, it’s not that.

Yes - S1.

My tier 2 colleague is now trying with the official Plex container as he wasn’t utilising it. 

Which made no difference. Still unable to reproduce.

@pwt would you mind creating a new test container with a new instance of Plex in it and test if that fails too?

Apologies for the delay responding.

I’ve just tested this issue again and I can no longer reproduce this either, despite the problem persisting for months previously with various versions. Seems like something has changed in the Plex/Sonos integration or something that was cached has expired (I’d restarted everything multiple times previously to no avail).

For reference, I’ve been running Plex in a Docker container on an Ubuntu server. External port access and NAT hairpinning are all fine.

I forgot to note what version of Plex I was running before, but it started working there. I’ve just updated to 1.25.6.5577 (which only has ‘preferred’ and ‘required’ as secure connection options) and it works in Plex internally (e.g. 192.168.x.x), in Plex externally (e.g. 80.x.x.x), via app.plex.tv and from Sonos. i.e. all seems to work everywhere so looks to have been resolved. For me, at least…

Others online have suggested to me to actually bridge the Plume pods as Wifi access points and switch back to using the ISP router instead, which is a VM Hub-6ax and should support NAT loopback (perhaps). It appears others have had success with this, but I prefer to stick with the Plume service at the moment because of other things that their service provides - I can still use the Plex service with Sonos through the native Plex App - it’s only the Sonos in-built plex service that does not work for me.

I think I’m just going to have to live with the issue, but would be nice if Sonos/Plume could resolve the matter and allow the service to work in the same/similar way as the Plex App itself. I have written to Plume Support too in the (now-distant) past.

Yes, still not working for me. Latest versions of everything.

Hi @pwt  

That’s unfortunate. If you happen to find anything out about what’s going on, please update us here. Thanks.

Just to briefly mention, I did liaise with Plume support over the (on-going) NAT loopback issue and now with the latest Plex server update too and assistance from Plume, I have Plex now working on all platforms including Sonos and can at last enjoy my Plex lifetime pass.

Great for when travelling/camping around the UK to be able to access my home music/media library and play to the Roam (or Move). So all’s well that ends well.

Chiming in to say I have the same issue as described above. It’s intermittent: from the Sonos app (S2 everything) I can browse music from Plex and start an album. Sometimes the whole album will show the error, one after another. Sometimes just a few songs, then randomly it will start playing one. Sometimes no issue.

I’m not on Plume, but Unifi.

Maybe try the Sonos system setup in SonosNet mode by wiring one Sonos device to your primary unifi Hub/Router and see if that may perhaps resolve the intermittent issue for you.

Errors during playback have nothing to do with the app: its the speakers that reach out to the Plex service. I already posted the list of supported ciphers. I don’t believe that list is different between S1 and S2. You need to ask Plex what is going on.

The OP has Play:5/gen1.