Can Connect Amp power rear surround speakers with Sonos Arc?

Can confirm they are all WM:0 @John B. I don’t know what that refers to but that’s what About My System says.

That tells us that your system is in SonosNet mode, which is the second precondition for using C:A as surrounds.  This results from the connection of the Beam to your router.  I wanted to check that was working because if it hadn’t been, we would have had our answer.

But that’s not it, so next thing to check is that cabled connection from Playbar to C:A.  Do you have another cable you could try for that?  Also try the other ports in the PB and C:A?

I’m having exactly the same problem. Two rear speakers via connect.amp, not working anymore since s2 upgrade. Both the playbase (in my case) and the connect.amp are wired to the router. Connect.amp is working perfectly standalone. In the S1 controller, when adding surround speakers, it would suggest a menu of possible sonos speakers to add (including connect.amp), which worked fine. In S2, when trying to add surround speakers, it immediately gives the error message that no wifi speakers can be found to add as surround… Frustrating...

@John B I have tried both of the solutions you suggest. No joy. Not even close. I am not a technical Sonos expert but I am confident of one thing: it is a software issue. When I try to Add Surrounds in the S2 app I instantly get an error message saying no WiFi speakers can be found. Just as @Michaelsmets reports. It does not seek a wired connection at all. It is as though it’s not an option. I don’t have a solution but as it stands Sonos has ruined my perfectly functional setup and in my view is trying to push me towards spending hundreds more pounds on an Amp that I neither want nor need. 

Perhaps now it is time to call Sonos Support again and see if they can take a look, and ask them directly if this set up is still possible.  If they say yes then they should escalate you through support until a solution is found.

This assumes it is not a failed unit, but they should be able to determine that.  

I have never known Sonos to shut off a possible setup without warning, and I still think that if they had there would have been a deluge of complaints not a trickle.  And we know that others still have this setup operational.  I could of course be mistaken.

You might like to draw Support’s attention to these current Sonos articles, which make no distinction between S1 and S2.

https://support.sonos.com/s/article/4807?language=en_US

https://support.sonos.com/s/article/2927?language=en_US

@John B Thank you for all your help. I will gird myself to speak with Support again and see how I get on.

You may or may not have seen this further thread 

https://en.community.sonos.com/home-theater-228993/did-the-s2-update-really-mess-up-adding-a-surround-speaker-6851341?postid=16491587#post16491587

I shall be interested to hear how it goes and I hope a solution will be found.

Thanks John. I’ll keep an eye on that thread. It’s exactly the same issue as mine, and in fact the response from Sonia support is exactly what I was was told (after two fairly long troubleshooting calls).