December 2025 S1 update - took down LAN amd WiFi networks

Untouched by you, perhaps. This doesn’t, unfortunately, mean no changes at all, from system updates on the Sonos and the router, much less all the possible changes that affect your signal from ‘outside’ your network, from things inside your house to things outside your home, 

Clients appearing and disappearing are often signs of simple wifi interference . In your particular case, beyond reading and acting in the linked FAQ, I’d suggest a simple network refresh. Unplug all your Sonos devices from power. Then reboot your router. Wait two minutes, then plug back in your Sonos devices. This will give you freshened systems on both your router (which also assigns IP addresses) as well as your Sonos, in case there is any issues with their OS. Give the Sonos a couple of minutes to reboot and reconnect, then open your controller, and check for updates in your S1 controller. That should normally resolve the issues that you’re experiencing.

If it doesn’t, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. Don’t post the resulting diagnostic number here, their lawyers get sensitive about GDPR.

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 Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

Placing your Sonos on another Vlan wouldn’t help, generally speaking. The controller and the Sonos need to be on the same subnet, that’s usually pretty hard to do, as well as the speakers needing access to the net. 

Are you reserving IP addresses? Use STP, not RSTP. I don’t recall the model offhand, but one of their routers is very misleading. There is an STP setting in the router, but the setting is a default passed on to the switches. Switch ports on the router do not support STP. You cannot wire any SONOS directly to those ports.

Thanks Buzz for replying,

I’ve checked on old / previous equipment and stp is / was selected on both.  The wired sonos devices were wired / plugged into one of the distributed managed switches (not directly into the router).

out of the 13 sonos devices only 1 unit (a p1) was wirelessly connected using unifi wifi (again that ap was not wired / plugged directly into the router).

when i have time i will slowly start connecting each sonos device (one by one) back onto the network and see what happens

thanks again

I should have added the ethernet and WiFi use strict mac address to restrict access.  Dhcp is active on the ethernet router for a limited number of user devices

The unwired Play 1 may be connecting to the Sonosnet from one of your wired to Ethernet, Sonosnet capabile, Sonos unless you have disabled Wi-Fi on all of the ones that offer it. That Sonosnet may also be part of your issues as the other Sonosnet capabile Sonos are aware of it.

Any Sub or surrounds will be using a hidden and private Sonos 5 gHz low-latency link.

I fooled around with a mixed wierd/wireless setup for a while but in the end my most stable option was having all Sonos use my Wi-Fi. The amount of data they are passing is minimal compared to a lot of my other devices so I see no impact from them.

I also tried a managed switch, saw little if any gain from it and it added complexity to my system that I am trying to simplify as I age and find tweaking bits less of a hobby and more of a chore.

Thanks Stanley_4
 

It looks like I’ll need to investigate the sonos wifi solution, I've always preferred devices (where possible) to use RJ45 due to thick brick walls and a relatively large geographic coverage area (even wifi aps).  I’m practical though obviously preferring a stable network - modern wifi is much faster, has greater bandwidth etc now anyway…..

anecdotal but I must admit the ethernet seems to be operating much more smoothly / quicker (streaming of video, cctv, large file transfers etc) than it did before things went south in December i.e. without sonos.  However, that could well be due to the new router and wifi controller.

I’ll have a play and let you know what happens.

thanks again

Stanley and Buzz,

thanks for your advice and comments.

i’ve now had time to individually check the sonos devices taking each off the lan and transferring them onto WiFi.

As you commented, it looks like it was the wired ethernet sonosnet that took down the entire network - I know very little about sonos net but from what I observed it suddenly seemed to create a constant ip loop or start to act  as a dchp server in early december.  With no changes to ethernet or wifi settings I can only think this was caused by a firmware update.

I think you were 100% correct - if possible sonos should only be connected to wifi and not ethernet - this from someone who prefers ethernet.

After a week or so of observing / using Sonos it is much more stable (best Ive seen in12yrs) as devices do not constantly need regrouping when you load the sonos app, or drop a connection when you're using the app / playing music.

My other multimedia devices (tvs, dvds and satellite etc) on both lan and wifi etc are also running more smoothly too without unexpectedly buffering or dropping out on 1gbps network (as they did before)

obviously I’ve updated the router and the wifi controller so that would have helped with network integrity and speed.  However, until I removed all Sonos units from ethernet and transferred them to Wifi the network (even using the new router etc) was broken and unable to function.

My takeaway from this is that Sonosnet / ethernet is best avoided, probably based on outdated ethernet programming and ultimately a liability.  Use Wifi instead - I never thought I’d say that.  
 

Thanks once again.

I’m suspicious that you had an issue with STP, but if the system is now working, live in peace. 

I'd lean to STP too, having a. Wired and wireless connection to a device that isn't properly integrated into the network leads to loops and instability. 

A part of the issue might be Sonos still using older code from their Linux kernel, been a long time since I tried to dig into that and doubt I'll ever make the effort again.

Hi Both,

Thanks for your replies.
 

I have to confess Im no network etc expert so take on board what you say.   It could well be linked to stp but I dont know what could have changed and how that changed would have occurred.  Im the only admin and with 180 clients I leave settings untouched when they work. STP was still selected when I followed up.  

As you say things are working again and much better than before tbh and I honestly believe Sonos is better on wifi.

Thanks again

UniFi best practice is to have all Sonos devices either wired or wireless. As all your Sonos devices are now connected via you UniFi WiFi you are now following UniFi best practice:

https://help.ui.com/hc/en-us/articles/18930473041047-Best-Practices-for-Sonos-Devices