My system (5 Ones, Playbase, Sub, Beam) just did the same thing. Happily playing From TuneIn on one set of Ones that then stops. When I look from the IOS App, it claims there’s no Sonos anywhere.  Open MacOS App and it’s all there. Reopen IOS App, and it’s all back.  

They seem to have really gone backwards with the last update of so. Alarms also randomly appear and disappear.  I’ve had to add the whole system back once  and partial system another time by reboot several missing speakers. All since around the first of April.

Seems like an issue in the individual controller ‘discovering’ the Sonos system on your network. If possible, 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, they 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.

Just as a note, there are several things unique to a device that is running a controller, like work profiles, VPNs and other apps which could ‘block’ the ability for the controller from reaching out to find the system, but I’m taking from your post, based on the ‘sometimes it’s the other way around’ that this isn’t the case, which is why I’m suggesting contacting Sonos. 

Thanks, I will try the diagnostic route. 
 

Chris

Thanks. I will do that next time it happens. It does seem odd that the more basic MacOS controller always seems to work, both for the system overall and for the alarms. Alarms are nearly always (but not totally) missing from the IOS app (both iPhone and iPad) nice the April update. My whole system worked flawlessly until that update, even through the initial “new app” mess last fall

​@MrWheelbarrow 

By chance are you using a modem/router box provided by your ISP and you have another router connected to the ISP equipment using the same SSID and Password for both the ISP gear and the other router?

If so, you have two networks, and both show the same SSID. Therefore, your Sonos is “network hopping”.  Assuming that is the case you need to have your ISP place the router portion of their gear in “Bridge Mode”. That will eliminate the ISP network and place Sonos and all Wi-Fi products on the same network.

Well, it could be the Sonos, or the phone (either of them). 

An interesting possibility ​@AjTrek1, I do have two wireless networks and can set at least the non-ISP one to bridge mode. One possible complication is that I also have a Boost that might be serving that purpose (or further confuse it).

Richard

I’d recommend setting the ISP router to bridge mode. I prefer to use my own router as I have more control and have the ISP router set to Bridge mode. No offense intended...but setting your personal router to Bridge mode and not the ISP’s kind’a defeats the purpose of investing in a personal router. JMHO 

The Boost would not cause such a problem as it is a proprietary 2.4Ghz band (SonosNet) and nothing else can connect to it except Sonos. You can still see your Sonos when it’s on the Boost network as it (without being too technical) piggy-backs on your home Wi-Fi which is why it must be wired to your router. 

However, outside of creating two confusing networks (which it doesn’t) the Boost is obsolete. Wiring a speaker to your router is the now preferred method when the SonosNet is needed.

Hi, just for clarity I do have a boost wired into the network, and my isp’s router is already set to bridge mode. 

Just been thinking about my set up. I think this started happening when I bought my Eero routers. I set my ISP router to bridge mode and hard wired the Eero into that. Then the other two Eero’s are connected wirelessly to the primary. 
 

However, the Eero cannot take anything hard wired so I still have my Boost connected directly to the ISP’s router. I wonder if that’s the issue? 

Correction - my boost is plugged into a gigabit Ethernet switch which is plugged into the Eero gateway. 

Try disconnecting the Boost.

But before you do unplug your Sonos gear. Remove the Boost. Then power cycle your router and let it come back. Next power cycle your device and connect to your network. Last plug in your Sonos gear and let them come back. It may take 5-10 minutes to complete the Sonos reboot. Open the App and check that all Sonos shows. 

Thank you I will try that when I get a spare 15 mins

Honestly, I’ve done everything multiple times to connect the Beam 2 in Living Room, including deleting App & reinstall, restarting system several times, etcd. blah, blah, blah.  I have an SE iphone, 5 yrs old which could be the problem.  BUT, both the Era 300 & Beam WERE working fine for a few months, then it was like DejaVu with our horrendous startup experience.  The App is STILL glitchy, intermittently doesnt show up on phone, but does stay connected to Apple laptop, thank God.  But the living room Beam 2 doesnt show up on the laptop Sonos App either now.  

So tired of this “cannot connect to server” error message, esp. when the CORRECT wifi network is up and running.  Other error message is “unable to sign in” ad nauseum.  Grant you the sound quality is better than anything else, BUT why after all this time, complaints. firing of CEO and others “responsible” for the App disaster is it still glitchy?  This is why people prefer and go back to systems like Bose with a controller that WORKS.  At first I gave it 30 days to get working right after we bought it via Amazon...it JUST made it but I had the boxes ready to ship back.  At times I wish I had.  

Get it right from the start...go past Beta testing….this App from the beginning was rushed and failed, as we all know.  Now you have post-it note fixes on top of fixes….gotta be a mess.   

Sorry to b**** but man this is one of the MOST frustrating experiences EVER.   

John Dolen

Moderator Note: Modified in accordance with the Community Code of Conduct

​@ParkerJD 

Have you ran a Sonos system diagnostic within 10 minutes of the occurrence(s)? If not follow the instructions here and call Sonos Tech support. Make note of the reference ID but do not post it in the community.

I did a quick fix last night which was just to connect one of the speakers to the switch with an Ethernet cable. Works so far, so I’ll see what happens. 

Hi

This has been resolved with help from the Sonos support team, but it was not a Sonos issue in the end. They realised that my iPhone was getting its IP address from a different DHCP server. 
 

This made no sense to me initially because I only had one DHCP server. Anyway, it turns out my Linksys router, which was in bridge mode with WiFi turned off, was still broadcasting its SSID and dishing out IP addresses. So I changed the WiFi name to something different and problem solved. 
 

Chris

Glad you resolved your issue.

However, why was your Linksys Router in bridge mode? Are you using a Plug n Play 3rd party Wi-Fi mesh connected to your Linksys router? Could you describe your setup. 

Hi

Yes, my Linksys router was in bridge mode because I have an Eero mesh. Both were set to the same SSID and even though WiFi was disabled on Linksys it was still dishing out IP addresses for some reason. 

Chris

​@MrWheelbarrow 

Thanks for the reply! 

I’m not trying to be critical; but your previous problem is very common among users adding a 3rd party mesh to an existing network.

Most mesh networks consist of three (3) components. Although they all look the same one must be configured as a Router (Hub) and the others as Satellites placed strategically throughout your home.

If you have an existing Router it can (in most cases) be moth-balled in favor of one of the Mesh units being setup as the Router.

Using the same SSID and Password as was used with the current router when setting up the Mesh is recommended for a seamless transition.

The link below details how a EERO Mesh is best configured. The example uses the least expensive/sophisticated of EERO mesh systems. The process also negates setting the existing router in bridge mode which in your case seemed to be an issue. 

https://support.eero.com/hc/en-us/articles/207937603-How-do-I-set-up-eero

Not being able to set the Linksys router in bridge mode IMO points to a defective router.

However, if one does not want to set their existing router in bridge mode ALL EERO units (or any 3rd party mesh units) must be setup as Extenders of the Linksys router with no DHCP capability to assign IP addresses. Trying to accomplish that with products from different manufacturers can be a challenge.

Once again it’s great you got your Sonos working!

See https://www.reddit.com/r/HomeNetworking/s/QvfX0MFfSa for an explanation on bridge mode. If your router is still transmitting an SSID it is not in bridge mode.

Been a while since I used Linksys but I'm pretty sure there is a router option to disable the DHCP server for ip v4 addresses.

Still going to a bridge mode should disable DHCP v4 and v6 as well as router advertisements for IP v6.

I set up the Eeros as recommended and obviously putting the Linksys in bridge mode should have disabled the WiFi, but for whatever reason it didn’t. However, once you put it in bridge mode the option to disable dhcp server is greyed out (ie bridge mode should do that). It must have been accepting connections still, which as mentioned suggests a faulty router.
 

Correction to my earlier post, I don’t think it was broadcasting the SSID as I only ever saw one WAP with that name, but must have been available to connect to. Still hopefully that router is going soon once I can upgrade my broadband as they are soon replacing the tin cans and string that connect my phone line to the BT network. 
 

Chris