Have you tried hardwiring a speaker to your router to see if that solves your issue?

While it my be a little inconvenient for some, you may want to make it a permanent solution if it work for you. 

I have 11 speakers in my home with 5 of them hardwired to my network. I never have connection issues.. even with the new app.

Thanks for your reply and suggestion - I’ve not as my speakers are all around the house and not in the same room as my router which has to be in the hall, sadly wouldn’t work for us and would be frustrating since we got the Sonos speakers to be wireless (which have worked for years and years fine) - hopefully it’s an app issue they have fix asap!

Suffering the same issues. I can play my S1’s via Airplay, but can’t get anything to work with the APP. I’ve done everything Kdm239 listed above and got the same result. Quite frustrating. 

Same issue and give up troubleshooting. I can’t begin to describe the countless hours of time wasted. Had a party yesterday and they stopped paying.tried multiple phones both iOS and android. Same issue. Tried every troubleshooting step including reset router.
Great speakers, incredibly bad app that is full of bugs.
SONOS - please fire your entire software development team and start over!

I have been down the same rabbit holes.  It appears that anything wired works….. anything wireless does not work.  The wired has too much latency but at least it eventually works.   The wireless just flat out won’t work.  I have a bunch of S1s that are now door stops and boat anchors.  

This has been going on for at least 6 weeks and it is surprising that the company has no fix after a very bad software release.   Sonos, please help!!!

It is incredibly disappointing that changing a router could render my hefty set of Sonos speakers garbage. What company can be trusted anymore?  Same issue. The published FAQ steps do not align with their own app. I hate Sonos but I can’t wish them failing because they already have.

Never had issues until the app/firmware rollout

1st it was the crappy app

now my speakers keep disappearing from my system and I can’t connect to them and even when I can it’s unable to work as a stereo pair

You should fire the team that ruined a perfectly great system.

cant say I’m willing to dole out cash to build my setup further

FIX THIS PLS!!

Hello,
I have a similar issue.  I have three separate and independent WIFI networks.  Each with their own Sonos system set of devices connected.

Since the app upgrade, I am having trouble switching from one Sonos system to another.  

Even though I manually re-connected each of the devices on each of the Sonos systems, whenever I move location (change WIFI network), the App displays  “No Products Found”.

If I then go to systems settings, with the option to Update the Network, I doesn’t see any Products.

It is frustrating.  It worked flawlessly with the Previous release of the APP (S1) on Android.  Is there a solution?

Just got a new router and had a similar situation, tried updating the network and was saying no products found. Even hard wired in one device but still couldn't update network on other devices and as soon as unplug ethernet from beam went back to no being even recognised. In the end I tried changing network name and password on new router to match that of previous router and it started working again. Which is great for home but also means cannot easily take move 2 on vacation and use on a different network if cannot be found as a product.