The S1 device ‘firmware’ will certainly not auto-update to S2 without intervention from a user. The products will only update to S1.. and that’s true, even if the ‘automatic update’ option in the Sonos App, is set to ‘ON’.

A user would need to be involved to switch the products over to S2. So assuming there has not been any user-intervention, your devices should still be running on the S1 firmware and in that case you should be able to add them back to your S1 App.

However it’s not clear what you may have done from your opening post. You mention that you ‘reset’ some devices.. was that a ‘factory reset’? - if so, what were their status LED lights showing when you went through the ‘Add Product’ process?

You might ‘likely’ be better off not resetting your products, but perhaps rebooting your router instead, as this might just be a simple IP address conflict caused by your routers DHCP server.

So I would at least perhaps try that option first of all.

I will also add that if you have factory reset all S2 devices and tried to create a new S2 Sonos System/Household, you will not ever see those devices in your existing S1 App, as they will be running on an entirely different Household ID… which is the best way to setup an S1/S2 ‘split’ system anyway.

I catagorically do not want an S1/S2 split..not sure why anyone would..since the whole point of a house wide sound system is that it is..er...house wide

I decided to split the System here, as I wanted the Arc and a Sub (Gen3) and keep the old stuff too, but I can still play music to both S1/S2 in sync, as I retained an Airplay compatible product in the S1 system.

Anyhow your issue sounds like it’s pretty easy to resolve. I would certainly start with a router reboot and maybe bring each of your Sonos devices back online one at a time. Perhaps start with those S1 products that work and then add (or factory reset/add) the devices that are missing using the S1 App.

Note, if any were upgraded to S2, accidentally or otherwise, they will still downgrade to any existing S1 Household, as long as you don’t have the S2 App installed on the controller.

Hope you can manage to sort it.

My S1 app no longer works (after 4years of working fine).  A message automatically comes up saying “you can control all your products using the S2 app.”  

When I open the S2 app, the message states “this product is not compatible with S2 app.”  Add this product to an existing S1 system.  BUT the S1 system will NOT work.  

This would b funny if it was not so frustrating.  

Advice???

Please don’t double-post. Sonos support are dealing with your problem on its own thread.