App volume sliders missing

Have you tried resetting the app and reconnecting to your system?

What happens if you force close and reopen app?

I’ve tried both restarting and resetting the app. Unfortunately after reopening the same volume sliders remain unusable 

If you have the latest updates in stalled, ( you may want to go into general settings and check) then try and hardwire a main speaker like a soundbar or a speaker that is not a surround or a Sub to see if that helps. If it does, you have some WIFI interference and you would need to troubleshoot it. 
 

Make sure you also have the latest iOS and are not using bata software

The latest firmwares are installed on all speakers. I’ve installed iOS 26.2 today, but still fails.
Unfortunately none of my speakers have Ethernet plugs so hardwiring is kind of a hassle. 
What I have tried is having a separate 2.4Ghz only SSID, however this still resulted in the same outcome. 

What speakers do you have? Are they all Eras or Moves and Roams? 
 

Can you tells us who your ISP is and what device you have for internet? There are issues with certain devices that users here can help with.

I have two era 100’s, a 300 and a move gen 1. I just read online that I can plug-in any usb c to Ethernet adapter into the era’s so I will try that later today. 
 

My ISP is Ziggo, but I put the provided router into bridge mode with my own TP-Link ER605 router behind it. 

Do you suggest turning off the WiFi for this device? I’ve seen people suggest this to not start a sonosnet 

None of your devices create SonosNet when wired.

I assume all rooms/speakers appear in the app if so I don’t think your issue is entirely network related. Although my suggestion will involve a router reboot. This also assumes  if using a mesh network that no satellite have DHCP  capability to assign IP addresses. I suggest you:

Uplug all Sonos

Reboot your router 

Delete the Sonos App

Reboot your device and reconnect to Wifi

Just for kicks check for iOS updates 

Plug in All Sonos and wait for them to reconnect to your network (about 5 minutes)

Re-install the App

Select Join existing system 

Accept all prompts (eg. Always allow and not just while using app)

Sign in with your credentials 

Edit

Click the Profile Icon

Go to Privacy and Security 

Make sure UPnP is turned on as shown below:

I’ve wired one of my 100’s (the zithoek one that keeps losing the volume slider) up to Ethernet and turned off WiFi on the device to force it to use the Ethernet. Ive restarted the device and checked that it does indeed connect over Ethernet in the omada controller. 
 

The volume slider worked again for about 15 minutes but has now returned to being unavailable again….

​@AjTrek1 So I’ve tried unplugging and rebooting everything as you’ve suggested. I even restarted my APs and switches aswel as the router. This all with upnp on, I’ve experimented before with turning this off, also without succes. 
 

Everything worked, for about 15 minutes and then one of the speakers (woonkamer this time) wouldn’t allow me to adjust the volume again…

Just to clarify all speakers are visible in the app, they can be grouped, can be muted, and play music just fine. It’s only the volume control that keeps going away. 

Ok…

What AP’s and switches are involved? Are the AP’s actually satellites for a mesh network or 3rd party devices that you added? Are the switches dumb or managed?

Sonos doesn’t play well with 3rd party AP’s nor managed switches unless you are well versed in networking. Even then Sonos may be problematic.

So I have Two EAP650 acces points. One is directly connected to my ER605 router. Also connected to this router is a SG2008P managed switch, from which my second EAP650 acces point is connected. All network gear is from TP-Link.  
 

Both acces points are connected with Ethernet cables and no mesh network is used. 
I use only a single VLAN and have no ACL rules setup. So everything should act as “normal” unmanaged network. 
 

I can see my home network is a bit more complex than a standard one, however I also believe it’s not that dissimilar for Sonos to not work. 

Just a guess but I think the access point connected to the managed switch may be the problem. I would suggest unplugging all Sonos and removing the switch. Connect the access point to your router (using a dumb switch if necessary). Reboot your router let it come back. Make sure your device is connected to WiFi. Plug in all Sonos and let them come back. Let us know the results.

So I had a TL-SG108E (semi-managed) switch lying around which I placed between the router and the SG2008P switch already in the system. The AP is now connected to that new switch. 

Everything is now running without problems for the last 6 hours, so that’s good news! One side node is that occasionally the old setup could run for some time without trouble. I’ve had a stints of about 3 days without problems before.

I’ll update if anything changes, for now many thanks for the help!

So if understand correctly the AP is connected to the semi- managed switch (whatever that is 😂) which allows the AP to bypass the managed switch. Correct?

You are correct, this way the AP bypasses the fully managed switch. 
 
About that semi managed switch, you’ll have to ask TP-Link about that 😂. They call it an Easy Smart switch, which means that it does have a web ui, but lacks the functionality of a fully managed L2 switch. Also see https://www.tp-link.com/us/support/faq/839/

Thanks for the info on the semi-managed switch 😂. So if everything holds up for a few weeks or month then we can probably conclude it was the managed switch causing the issues (as I suspected). If not then it’s back to trouble shooting 🤔.  Let us know in a few weeks or a month if everything continues without issue. Good Luck 🤞!