The problem is that the downgrade process to S1 in the 16.1 app also checks if there is a new app version, which there is (i.e. the v80). And it says you need to upgrade the app to that version before you can downgrade your device. And that version v80 doesn’t have the downgrade option. So you are stuck !! 

I just stumbled into this problem.  I have an old S1 system with plenty of play5s throughout my house, and wanted to get a Move for outdoor use. I chose a Move 1st gen as it is listed as being S1 compatible.  It arrived today, and I spent forever trying to get it to downgrade, reading many threads, only to learn that apparently this feature has been removed in the current Sonos (S2) 80.xx app version and isn’t possible in the S1 app.  I couldn’t even get it to finish set up as a separate S2 system by itself, as it would immediately recognize the speaker, but then it would later in the setup process give an error stating it couldn’t connect with my mobile device despite it having found the speaker moments earlier.  I decided to give up on my iPhone and pulled out an old iPad air I have running iOS 15.8.2.  I went to download the Sonos (S2) app on it, and it told me due to the older iOS version, it would have to download an older version of the Sonos app. It downloaded Sonos 16.1.  When I opened it, immediately there was the box at the bottom for “other option” including downgrading a product to S1.  After following numerous onscreen prompts, it allowed me to downgrade my new Move to S1 today.  I was then able to quickly set it up with my legacy S1 system using my iPhone without a problem!   I’m realizing I lucked out having an old iPad to be able to complete this downgrade now by forcing an older Sonos software download from the app store.   So if you have an old iPhone or iPad accessible, try using that to downgrade and complete setup!

Or, you should just have stayed on S1 in 2020.

I remember Sonos devotees saying then that the S1/S2 thing was something Sonos was forced to do after 15 plus years, and in going to S2 there was no need to fear that such a dislocation would occur again in a shorter arriving future.

Famous last words that I am glad I did not take in.

I have now tried with your exact steps but it is now impossible to revert back to S1. Everything in your screenshots works just until after you have selected the device to downgrade to S1, it needs to check if it is the latest version. I have tried blocking Internet access etc but it will not pass if it can’t check and will not pass since it is not the latest version.

I guess you made the downgrade in the exact right time.

Here are some steps to downgrade a Sonos product from S2 to S1 which is a bit of a pain but I managed to pull it off:

1. Reset the Sonos product
2. Download the Sonos S2 app for iOS or Android
3. Open the app
4. Select More options when prompted to set up or join a system
5. Select Downgrade product to S1
6. Follow the instructions to downgrade the product's software 

Do not follow the direction SONOS has posted as they do not work and also I ended up resetting the S2 App in order to get the above steps to work.

The S2 to S1 downgrade tool has been added in today’s app update.

You are 100% right! In hindsight I wish I would have stayed on S1! All the time I wasted chatting with Sonos support and sending them my log files because my Sonos Connects would drop out one at a time but yet signal was excellent between them and they would say the same thing… reboot them… yeah rebooting them fixed it for a day or two… plus I had not had to reboot them before the poor S2 downgrade! And then there were my missing playlists from my S2 Android app that they said had to be a problem with my phone even though the playlists worked fine on the desktop app and if I forced closed the S2 app they would actually sometimes come back! Also the S2 app was so slow and when I woke my phone it would not connect to my system instantly to mute or pause music to take a call or talk to someone… S2 took a long time to connect and was just plain slow and painful!  

A whole week now back on S1 and guess what!!! not dropouts, playlists always show on my phone each and every time I want to play them and same as the desktop app, when I wake my phone from sleep the S1 app show instantly what is playing and allows control of the system... oh and did I mention I can run the S1 app on my old iPad mini!! Couldn't do that with the S2 app! 

Yeah I was a sucker! I believed Sonos when they said “S2 is the best thing since sliced bread” and I suffered for 4 long years hoping it would improve. NOT

So happy to be back on S1 which is what I used for the entire existence of Sonos as a company except for the past 4 wasted years of my Sonos life. 

There is another benefit of remaining in the quiet S1 backwaters and being of no interest to Sonos. 

I am seeing some threads referring to EULA that posit that Sonos may be taking control of your Sonos kit via the new courageous app. Even if they are doing this via a new EULA, this is still a heist. 

Stay on S1, present version; don’t even update within S1 and I don’t see that Sonos can then steal your speakers from you by taking control of them via the new app.

@SirDigitalKnight I think you downgraded to S1 just in the nick of time 

At the moment there is no way to downgrade to S1 anymore, at least not on Android. The v16.1 app asks to upgrade to the newest app version before allowing to downgrade a device. Even if you have disabled auto update for the specific app AND even for the complete Play Store.

Thank you so much Alan! I found an old iPhone and it’s worked a treat. 3 weeks of pain now sorted!

Sadly the new version of the Sonos S2 App (v80) has taken the roll back option away

Thank you AlanSanDiego - I found an old iPhone 7, did a factory reset, found the new “Sonos” app on the Apple App Store, and it was unable to download the “Sonos” app v80 (the iPhone 7 being before iOS16 which is required for the latest version) and instead downloaded the old “Sonos S2” app.  The S2 app immediately showed the downgrade option as per the Sonos help screens.  I now have a second-hand Play:1 working on my S1 system.   Having been very, very grumpy with Sonos for a few hours (well I still am actually) I’m very grateful to those who have used this forum and have helped me sort this.

I have never left S1; I stopped buying Sonos hardware after the S1/S2 forking, so I don’t know this in detail, but there are new Sonos products that cannot be moved back to S1 from the time they were released.

Also, I don't know if Port is in that category, but if it is, the said Port will never be able to go back to S1.

Thank you Stanley. I’ve got some older devices which can’t be upgraded to the new app. I therefore need to have all my devices on S1.

I had  tried to downgrade the Port to S1, following the instructions at the link you sent. However in these instructions it says “Sonos app version 80.0
The ability to downgrade a Sonos product to S1 is temporarily unavailable, but will return in a future update.”

I’m not sure how long this feature will be unavailable for and whether there is another way of downgrading the Port.

The other GREAT thing about S1 vs S2… NO MORE ADs!!! I hated the popup ads on S2. I would go to my tablet to skip a song or adjust the volume or group rooms and there would be a GIANT AD “Listen to Holiday music for that festival mood!” or “The latest Sonos Product model CR7#5#%3*2AP is here!” “Come spend your money on it! Click here!” 

Not seeing that crap anymore!  Oh the joy! 

All update privileges for Sonos have been locked down!  I only recommended Sonos to one of my friends.. ok… I only have one friend … and I feel sorry for him as he has Sonos at all 4 of his home locations and he uses an iPhone.. but I think he will be ok as he only listens to Spotify so he should be able to just use the Spotify app for most of his day to day operations.  

Thanks for confirming that it is still possible to upgrade to S1! I figured it had to be still possible but didn't want to chance going back to S2 on my system just to test the theory out.

I was able to downgrade a new Move speaker to S1 using an old iPhone 7!!!!  (The challenge for me as a longtime Android user was finding one, but you can find anything on Amazon … and it is returnable ;)).

You can't. At least not on Android S2 16.1. When choosing downgrade you need to login to your account. The next step is to check for updates. If the check fails you get an error message. So the version check is mandatory :(

Thank you so much for this Alan!

I’d tried getting an old version of the Android app from apkmirror to work on my daughter’s old Samsung tablet but it kept failing to install. Just stumbled across your post and gave it a shot on my old iPad Air 2, which is running iOS 15.8.2. It came up with the same message you received and proceeded to download Sonos 16.1, which has enabled me to downgrade my new Move to S1 so it will work with the rest of my system.

Was really worried I was going to be stuck with a fairly useless device until Sonos added the downgrade functionality back into the latest app, for which they’re not currently quoting any timescales.

Thanks again!

Yes, you would want to turn off “App-auto updates” in the Google Play Store before beginning any of this process and you might need to turn off your internet access if the side loaded 16.1 is trying to go out to Sonos for an update and stopping you from this step in the process of rolling back but I doubt it as I just tested this this very moment after installing the 16.1 version (sideloaded) and it did not try to update my app and I took screenshots of the entire process which I have attached below with comments under each screenshot to make it simple, but since all my gear is on S1 it did not find anything to rollback so I could not actually show you it doing the rollback to S1. Again, I just tried this today 5/15/2024 7:00am EST and it worked just fine.

So step number one is turn off of “Auto-update apps”. If your S2 app was already updated to 80.0 uninstall it then side load the 16.1 version of the S2 app then factory reset the device or devices you want or need to upgrade to S1. After you are done upgrading your system to S1 you can uninstall the sideloaded S2 app and turn back on Auto-update of apps. Google Play has “Auto-update apps” a bit hidden so I have attached a screenshot of where to find it in Google Play store “Setting” under “Network preferences”:

If you get stuck at this point try unplugging all but one device. The device does not need to be connected via network cable. Just plugging into power and should have the green LED blinking if I remember correctly as it has been a week since I did mine and I am very old. On my first unit it did pop up and say it failed to install S1 but it actually did work just fine. It will also tell you it needs to connect to the WiFi of the Sonos unit to do the S1 transfer and will show you what the Sonos WiFi looks like. On my first unit I had to manual connect to that Sonos WiFi signal on my phone to install S1 but on my second unit it automatically connected to the Sonos WiFi signal for me and install the S1 onto it and when finish said it was successful. Sorry I did not take screenshots of when I did the actual downgrade last week to fill in after the steps I have shown you above. I also will not be trying to go back to S2 now as it looks like they are forcing firmware updates to systems that are on 80.1 so if you have already updated to 80.1 I think you are S.O.L.  

Having the exact same issue here.  Looked for Sonos S2 app, does not appear to be available, just an app called Sonos now.  Effectively, now I have a Sonos Port paperweight.  Any ideas on how to downgrade to S1 so it can be used?  Thanks.

So then might not the OP do a factory reset of the Port and add it to the S1 app? Failing that, return it for a refund, get a new one and add it to the S1 app?

It is symptomatic of Sonos stupidity that new brave new app has caused such actions to be required at the user end, assuming that they work.

A week ago, reverting to S1 was easily done for the Port. Even that has been hamstrung now.

Thank you Stanley. I spent an hour getting the Kuhn to customer service yesterday who said that the future to downgrade to S1 will return in a future version of the app but they couldn’t give me a timescale. So the shiny new Port will have to stay in its box for an indeterminate amount of time until that day Customer service at its best.

Installing an older version of the app using the app mirror service you trust is no problem. The problem is that older apps were programmed to ask for app update during the downgrade process and therefore installing an old app results in having to upgrade app before downgrading device.

Maestros!