Assuming they are Sonos HT surrounds to either an Arc, Beam etc; then they do not connect to your router, for the most part - they will connect direct to your Sonos HT master device instead via an ad-hoc 5Ghz wireless connection. So maybe next time try powering off/on the Sonos HT master (Arc/Beam etc.) and see if that resolves your issue.

What might be helpful to prevent further issues, is to add your Sonos products IP addresses to your routers DHCP reservation table to make them static.

Thanks Ken.

I got so far as to unplug and restart the Arc. The surrounds were visible, but then when I went to 'add surrounds' in the app, I kept getting the message that 'There was a problem adding your surrounds' and so on.

This is doing my nut in!

HELP!!!!!!

They should add themselves to the Arc - it might have been the case your App was not refreshing and showing you the true picture of what was going on, so maybe also try fully closing the Sonos App (sliding off screen) and reopening it next time - whatever you do, do not ever opt to factory reset your speakers when this happens, as that’s really only ever necessary as a very ‘last’ resort and it is unlikely ever going to resolve the issue described.

Also, if you know how to do it, don’t forget to reserve your Sonos IP addresses in the routers DHCP reservation table, as that may possibly assist with your issue.

Finally sorted.

Thanks so much for your help, Ken. I really appreciate it.

What did you do to sort it, @Kopacabana? It’s always good to know how a problem is resolved. 

I followed Ken's advice by unplugging and restarting all the speakers. The app then found the two SLs and it linked them back into the group without a problem.

Ken's helped me understand the mindset that the Arc is really the hub and not the router.

I suspect it may have been duplicate ip addresses when the router restarted and tried to allocate IP’s again. It’s always best to restart the speakers too after a network restart. Or allocate reserved addresses for Sonos devices, which should avoid the need to reboot them. 

How do I allocate an address?

Yes.. I’m curious also on how to do this. 

Each router is different unfortunately, but often it’s a case of using a web browser (or an App if the router manufacturer has an App) and logging onto the router at the gateway IP address, usually it’s something like http://192.168.0.1 or similar.

login with username and password (usually printed on the back of the router, or shown in the user-manual) and then it’s a case of looking through the settings to see how to set the Sonos IP addresses as ‘fixed’ or ‘static’. Often there are videos on YouTube to help provide the info. on how to do these things, so perhaps search for your router and how to reserve an IP address … or checkout the router user-manual.

A Sonos products current IP address and MAC address can be seen in the ‘About My Sonos System’ area of the Sonos App in ‘Settings/System’, which may assist.

I chose to reserve my IP addresses high up in the subnet. So just as an example:

1. Sonos Boost - MAC AA:AB:AC:69:28:E0 - IP Address 192.168.0.100
2. Kitchen One - MAC AC:28:F9:24:E0:24 - IP Address 192.168.0.101
3. Lounge Arc - MAC 28:C6:E1:32:F7:21 - IP Address 192.168.0.102

etc. etc.

When adding the addresses, do not forget to press the save button to save the settings to the router too. From that point forward the allocated IP address will then always be handed out to the Sonos product and so help avoid any duplicate IP address issues when the network is rebooted.

Anyhow, I hope the above summary/example information assists you to get started with reserving your otherwise ‘dynamic’ network addresses.

I think I'm done with all of this.

Right surround decided to disconnect today for no reason. Back to spending hours trying to reconnect.

I can't reserve IP addresses as my admin router access/IP won't allow it.

I really can't understand or qualify how an audio 'expert' like Sonos can deliver great sounding products but with piss-poor connectivity. This is basic stuff and makes me regret my decision to invest my cash.

When I do manage to get the speaker reconnected, yet again I'll be nervous, waiting for when things go wrong again.

A truly miserable experience.

Simple solution, surely: buy a different router. 

I shouldn't need to.

A number of quick things… 

• What make/model router is it?
• Anything ‘wireless’ near to the surround that has ‘dropped’ out?
• Are you absolutely sure the surround has dropped and it’s not just an SSDP multicast ‘discovery’ issue by the controller device - perhaps just check to see if the ‘surround’ is still on the LAN by ‘pinging’ it’s IP address. It might just be your controller is displaying incorrect information to you (also see if it still plays audio) I suggest trying some music to the room, that’s if you have the surrounds set to ‘Full’ playback for music in the HT room settings.

@Kopacabana,

Well you only have to search the threads here to see the issues with BT routers - I seem to recall those routers have issues with multicasting discovery when devices are operating across the two different WiFi bands (2.4Ghz and 5Ghz).

This is my personal suggestion, but it’s a matter for yourself if you want to try this…

In the router configuration pages, from memory, I think there is the option to uncheck a box on the WiFi page (I think it’s called something like ‘Smart WiFi’ or similar). Either way, there is then the option that allows the user to separate the two WiFi bands and give them each a different SSID .. I would do that, but note it may affect some other devices on the LAN, but first see this…

As a temporary measure (and as an initial test), rather than rename the bands - just separate them and simply switch off the 5Ghz band for now and see if all your Sonos problems go away (give it a few days to test this).

If that works, next re-enable the 5Ghz Wifi band, but give that band only a different SSID and then anything on your network you want to use on that band (not Sonos) just set them up again on that band. 

Hope those few suggestions are easy for you to follow.. oh I’m fairly sure that router does allow IP address reservation too, so definitely do that with your Sonos devices when you perhaps get chance to do that (non-urgent and optional, but worthwhile).

I haven’t watched it, but this YouTube video I found, may perhaps prove to be useful to you too…

Thanks Ken. I see what you mean!

Could you recommend a router for me to buy? I trust your opinions and advice. Without sounding outrageous, money is no object - I just want to tech the best solution to avoid these headaches!

I’m certainly no expert on routers with Sonos, but maybe others will chime in and say what they use. I personally use a 6 hub Plume mesh WiFi setup, which does comes at a price (plus there are yearly subscriptions involved too), and it can be difficult to troubleshoot if things do go awry:

https://uk.pcmag.com/wi-fi-mesh-networking-systems/134725/plume-superpod-with-wi-fi-6

That said, I would save your money, as there are the options mentioned to switch off the routers 5Ghz band and you could even try your system setup in SonosNet mode, as mentioned in this link:

https://support.sonos.com/en-us/article/switch-sonos-between-a-wireless-and-wired-setup

Many thanks, Ken. Your advice is very much appreciated. 

Thats ok, Looking at that YouTube video, it’s seems quite an easy task to toggle off the 5Ghz WiFi band (only) on the router. I would just see if that fixes things for you, if not, just switch it back on again, but try it for 24 hours or so and see how it goes. It shouldn’t do harm and it’s easy to reverse the setting too.

I can’t rule out however that the software on the router may have changed slightly since that video was made, but it should at least be similar.

Reboot all the speakers if one of them does go offline.