Sounds like a local WiFi issue. Could be simple wifi interference, or more. I’d start with a simple refresh of the Sonos network: unplug all your Sonos devices from power. While they’re unplugged, reboot your router. Once the router comes back up, plug back in the Sonos devices.

If the issue continues, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, 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, there are more options available beyond just the diagnostic analysis.

It’s not a wifi issue. This keeps happening with Sonos and for the price you pay I expect better. Currently I can’t play through some devices at all (but it keep randomly changes which ones will play). I’m going to reset my wifi. And restart all my Sonos speakers as if they were new. Such a waste of time and effort. What’s annoying is that the Sonos app won’t recognise some of my devices (but at the same time recognises others, so clearly not the wifi) but my IPhone will allow me to send music to each device (although having issues playing on multiple devices, even though they show as available). This was all working 100% fine this morning. 

The issues are so terrible now. My tv will play through beam, but won’t play through the surround speakers. Because beam isn’t on the app I can’t do anything. Have connected via Ethernet and it sets up fine but beam keeps disappearing. So basically I’ve got a crap sound bar that I can’t join up with anything else. 

@Nortypony, Is it possible to wire the Beam permanently to the router (NOT the surrounds)?

I connected beam via Ethernet. All set up ok. Re added the surrounds. All ok. Plugged in hdmi for tv and now all devices have disappeared from Sonos app. Nothing showing as connected. Can’t connect to any devices. This is an absolute pile of crap. Spent 2 hours trying to just get sound to work and still no joy. Will have to just disconnect all devices, power them off, completelY rest and try tomorrow 

A factory reset of the Sonos hardware won’t resolve underlying networking issues. I advise you to get in touch with Sonos Support by phone.

Yeah I’ll try when they open again tomorrow. So frustrating as I’ve literally reset everything as if I was a complete new Sonos customer and it just won’t work. What a complete waste of money this whole system has been, as now I have 5 devices that don’t work together - and some not at all. Thousands of pounds wasted 

The fact you keep resetting them is exacerbating the problem.  You have network problems, more than likely duplicate IP addresses due to the router rebooting.  By resetting your devices, they are just getting another IP that is already in use.  You need to do a network refresh so the router hands out new addresses to all devices. Otherwise the problem returns every time an IP lease expires.  Reboot/power cycle the following, in this exact order, waiting till each comes up before moving to the next:

Router/modem

Switches/hubs

Wired Sonos devices

Wireless Sonos devices

PC/Laptops/streaming devices

Printer and other peripherals

You can also switch WiFi Off/On on your phones/tablets

After that, you can eliminate the problem entirely by going into your router setup and reserving IP addresses for all you Sonos devices.

This is all just gobbledygook to a layman. I’ve disconnected everything and reset everything. Why does this have to be so complicated? Despite months of everything being absolutely fine, for no reason, my whole Sonos system doesn’t work. Every other wifi device (like my TV and computer) is working fine, so there is no issues with my wifi. 

Have you contacted Sonos about this?

They’re closed just now. I’m guessing all they’ll do is make me go through the exact same steps I’ve being doing. Can they actually fix faults remotely? 

Your TV and computer is not required to group and play in sync with other TVs and computers resp. Trust me, you are experiencing network issues which need to be resolved.

Do you wish to rant?  Or do you wish to get your devices working?  If the former, I’ll leave you to your ranting and go help someone who actually who wants help.  If the latter, tell me what is “gobbledygook” and I’ll try to explain it in better terms.  But please, choose rant or fix, and only rant or fix, because I’ll not waste my time listening to your whining while I’m trying to help.   If I want to hear whining, I’ll babysit my grandkids.

It isn’t network issues. I am in my bedroom now, and my Sonos move is responding to voice assistant and connecting to internet requests (I can ask it to play radio etc). However, my Sonos app can’t find the device. My Sonos add also can’t find my other devices, even though I can send music to them from my iPhone. This is clearly a Sonos issue. The problem I have is because I can’t link my devices through the app, my beam and surround is redundant. I can ply my tv through the beam and that works but can’t add surrounds. 

Classic symptoms of duplicate IP addresses, which are (You guessed it!) a network problem.   So let me ask; do you wish to get it working, or do you wish to stubbornly keep insisting it’s not a network problem?

That’s great, but how do I deal with duplicate IP addresses? I have no idea how to deal with this. I simply have a router and a few things connected to it. I have disconnected all my Sonos devices, in the app I have selected forget network etc. So now when I open the app it shows nothing in my system. I have run diagnostics on my router and it shows 2 Sonos connections (but from what, I don’t know, as they’re all disconnected). I’ll accept its a network problem but why is everything else working absolutely fine, but my Sonos devices are not? 

I have been gathering experience in troubleshooting Sonos for over five years. As a first read through Reduce wireless interference, as a second through Speakers missing from the Sonos app.

Power up your computer prior to calling Sonos.

Well, first of all follow the steps I outlined above, in the exact order listed.  Second of all, give us the make and model of your router and we can walk you through reserving IP addresses for each Sonos device.  It’s not much harder than changing your WiFi password.

And the reason everything else is working is because they are standalone devices that do not have to cross communicate.  So if one or more have the same IP, it doesn’t really affect anything.  But since Sonos devices interact, both with each other and with the app, having two with the same IP address causes them to disappear and reappear in the app because the app sees one IP for multiple devices and gets mixed up.  

I’m sure you mean well, but my mind is blown. I’m literally just a normal non-techy person who has bought some speakers. Connected them to my wifi and enjoyed sound - both connected and controllable through the app and works with my tv. Today, half way through the day, my app now won’t show any devices. One of them is still working with my internet connection. I just have a bog standard Sky router for my broadband. How can speakers for normal people require techy solutions to make them work. 

Ok. No rant. 
 

1. Disconnected all Sonos devices. 
    
2. Restarted router
3. Deleted and resinstalled Sonos app 
4. when app opened, selected new system (other option is to join existing system,  but app said can’t find existing). 
    
5. went to system to add new product 
6. plugged in Sonos beam 
7. app recognised beam 
8. I pressed button on back of beam as instructed 
9. app said connected. The said attempting to connect to wifi 
10. failed 

App now shows message at top saying Unable to connect to Sonos. 
the options are to power off and on. Done this a few times 

I just re set up, speaker by speaker. Sonos 1 in the kitchen. Done. 2 x Sonos One SL done. All working together. Showing in app. 
 

Added Beam (via Ethernet, as wifi can’t find). Says connected. But then fails and now Sonos app has removed all speakers from app. 
 

I only wish I had found this about 4 hours ago. Really not technically minded and haven't ventured into saving ip address yet but at least I have music, for the moment.