the new app doesn't work ever

The chance of them ‘bringing back’ the older app seems to be zero.

Have you called Sonos Support directly to discuss your connection issues?

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

Currently on my third phone call with Sonos.  When and if the app responds it is intermittent.  After I try to increase the volume the app takes it back to zero almost every time. 

During the second call, the recommendation was to delete the app.   It’s hard to control the system fully w/o the app.

I think it’s time for a new system.

With that type of behavior, and not having access to any further data, I’d diagnose an issue with the local network, where your controller is unable to maintain a constant connection to your speakers. The first thing I’d try (especially since I’m not having a similar experience) is a network refresh, by unplugging all Sonos devices from power, then rebooting the router.

I would give the router a couple of minutes to get back ‘up’ before plugging back in the Sonos devices. This will force the Sonos devices to both reload their own OS, as well as requesting new IP addresses from the router, which has been refreshed on its own by rebooting it.  Doing this process would certainly not hurt anything.

But it could also easily be relatively simple wifi interference . I’d have thought the data in a diagnostic, which can only be looked at by Sonos personnel would identify this, but as I don’t have access to that data, I’m not sure. All I do know is that I’m not experiencing the same issues that you are.