Volumio 4: Troubleshooting Multiroom Grouping

I’m having issues with Volumio 4 and multiroom grouping. I have two identical Raspberry PI 4 boards and a Raspberry Pi 2. When I start grouping from one of the Pi 4 boards the grouping works. But when I started it from the Pi 2, it was not working. Now when I look at the grouping popup from the Pi 2 I see “No groupable devices found”. But from the Pi 4s I see all the devices and can do a multiroom sync.

So I’m curious what the mechanism is that determines whether a device is “groupable” and how to better troubleshoot that functionality.

Do all the devices run Volumio4? Are all devices enabled in myvolumio?

If possible could you send a log from the PI2?

All the devices are running 4.071. They were all initially flashed to 4.067 and upgraded automatically.

Logs uploaded here:

logs.volumio.org/volumio/Tpyqy4I.html

I actually think it might have resolved with the latest update. Now I’m seeing when a device is in a group “grouping” on that device is disabled. When I remove it from the group it’s contained in, grouping becomes possible again. It would be nice to know which device in a group is the “coordinating” device for changing things around.