I think there is a bug with switching the multiroom devices in volumio3.
What works:
Volumio3 on a Raspberry with a audio dac. Connecting from external device (mobile phone for example) to the webpage. All is fine. You can conntect to the IP of one volumio device and from there you can switch with the “Multiroom” option to all other devices and back to the starting device.
What does not work:
Volumio3 on a Raspberry with a dac and a display. The same thing, but now connecting directly from the raspberry (with the display) to the webpage. This works no problem, but when you switch via “Multiroom” option to another volumio device, this works, but you can never switch back to the starting device (with the display connected, so in fact the local device).
And, maybe a hint: Before switching, you see the pictures of all other multiroom devices, but the local picture is not shown (in the multiroom overview).
So it looks like there is a problem with the local URL or something like that.
I think we had the same issue during beta testing, but unfortunately i can not remember exactly.
Edit: Ok, looks like i found the fix which i remember:
But it is installed and does still not work.