Sonos and Webcore - 5.1 setup only showing one speaker in Devices - does not play

I have a Sonos Playbar, Sub, and 2 Play:1’s in my living room. They are linked together for a 5.1 setup in the Sonos app. Separately, I have a standalone Play 1 in my bedroom.

Everything works fine when playing from the app or from an optical source into the Playbar.

I am trying to use Webcore to set volume and play track ( The piston works perfectly when I point it to the bedroom (standalone Play 1). When I point it to the living room, set volume works (checked in the app), but it does not play. The app shows stopped, and the previous source still appears on the room screen.

In trying to troubleshoot, I found that the living room “device” shows up as a Play 1 in My Devices. The only two Sonos devices I see are “bedroom” and “living room”, both of which appear as Play:1 devices. When I look at the Events List for the device, I can see the piston is sending the command to the speaker, but the speaker does not play.

The fact that it works perfectly when pointed to the bedroom tells me that the piston is set up correctly. Am I wrong?

I would think that the living room device should register as the Playbar and this could be the source of the problem. I could also be waaaaaaaayyyyy off base with this.

Any suggestions?