I just downloaded Volumio today (so it’s the latest) and have it working on a RPi3. I was connected to it via wifi and looked at the network settings. I noticed the ethernet connection was saying it was set for a fixed IP, and not only that, it was the same one as the Wifi. I knew that wasn’t right, so I switched it back to Auto (dhcp).
Unexpectedly I lost connection to it via the Wifi, but I thought OK, it has restarted all the networking, so I waited, thinking it would reconnect to the Wifi. It never did. I had to power the RPi3 down and reboot. It immediately connected to the Wifi, and is working again.