Not possible without significant difficulty, namely converting the speaker-level outputs of the Connect:Amp to the line level inputs required by the Cyrus. The Connect:Amp has no line level output.

A clumsy solution would be to find a speaker switch that allows you to switch your speakers between the two amps.

The more streamlined solution is to replace the Connect:Amp with a Sonos Port or second-hand Sonos Connect (making sure you obtain a Gen2 version if you want to run Sonos S2 software).

Thank you pwt!!! Not what I wanted to hear but great and valued response nonetheless!

Sorry @pwt: one more Q: what allows the Connect to do that but not the Connect:Amp?

The Connect:Amp and Connect serve different purposes.

The Connect has a line level output, since its primary purpose is to be a streaming device connected to external amplification. It is not an amplifier, and cannot drive (passive) speakers on its own.

(Arguably, Sonos could have furnished the Connect:Amp with a line level output in addition to the speaker outputs, but they didn’t.)

@pwt OK, I think I get it. Thank you so much. So I presume a Gen1 version would do the same? I’m just using it in my office and the S1 app is fine out here.

A Gen1 Connect would work fine, as long as you’re happy to remain on Sonos S1. I have three of them still going strong.

They’re available reasonably cheaply now on eBay, etc.

Thank you, very helpful!