I have two Volumio devices, volumio-livingroom (192.168.210.26) and volumio-kitchen (192.168.210.27), running as a Multiroom group.
After running normally for some time, the group disappears. The second device is still visible in the Multiroom UI and the “Add” button can be pressed, but it does not join the group.
Rebooting the devices fixes the problem. I have now found that rebooting is not necessary: running
sudo systemctl restart volumio
on the affected client (volumio-kitchen) is sufficient. Afterwards the client can immediately be added to the group again.
Likely trigger identified in logs
I was able to find the exact moment when the working group was lost.
At 20:27:55 the Kitchen device had a short Wi-Fi disconnect:
wlan0: CTRL-EVENT-DISCONNECTED
dhcpcd: wlan0: carrier lost
avahi-daemon: Leaving mDNS multicast group
Discovery: A device disappeared from network
The Wi-Fi connection recovered a few seconds later. Volumio then successfully rediscovered and reconnected to Livingroom:
20:28:08 Discovery: Found device Volumio livingroom
20:28:08 Discovery: Connecting to remote: 192.168.210.26
20:28:08 Discovery: Connected to remote: 192.168.210.26
However, immediately afterwards Volumio removes Kitchen from Multiroom:
20:28:09 MRS: Removing this device as multiroomSync client
20:28:09 MRS: Setting this device as single
20:28:09 Setting Multiroom Single
20:28:09 MRS: disable multiroom output
and finally:
20:28:11 MRS: STOPPING SNAPCLIENT
systemctl stop volumioSnapclient
snapclient: Received SIGTERM signal
Additional observation
When trying to manually add Kitchen to the group afterwards, Snapclient actually connects successfully to the server:
Connected to 192.168.210.26
but Volumio immediately issues:
MRS: STOPPING SNAPCLIENT
and executes:
systemctl stop volumioSnapclient
Therefore this does not appear to be a Snapcast connectivity problem. The client can reach the Snapserver, but the Volumio Multiroom state appears to remain inconsistent after the temporary network interruption.
Restarting only the volumio service on Kitchen clears this state and Multiroom works again.
Network
FRITZ!Box 5590 Fiber with two additional FRITZ!Mesh repeaters. Temporary Wi-Fi interruptions/channel changes can occur. The important issue appears to be that Multiroom does not recover correctly after connectivity has been restored.
Expected behavior
After a temporary network interruption, the Multiroom group should either automatically recover, or it should at least be possible to manually add the client to the group again without restarting Volumio.
Actual behavior
The client remains visible, but cannot be added until the Volumio service is restarted.
Logs
Kitchen: http://logs.volumio.org/volumio/6Bq88O0.html
Livingroom: http://logs.volumio.org/volumio/0GNvLVR.html
Environment
Kitchen device/model: Raspberry Pi 4 Model B Rev 1.5 (WLAN)
Livingroom device/model: Raspberry Pi 2 Model B Rev 1.1 (Ethernet)
Volumio version Kitchen: 3.912
Volumio version Livingroom: 3.912