I searched the forum but did not see this issue. Playback zones are not working for my installations. I have 2 RPi running the latest version of Volumio (2.729). One is named VOLUMIO-DESKTOP and the other VOLUMIO-MAIN. They both have fixed IP addresses and connect via WiFi. For a period of time this feature worked fine but over the last two updates it has not. This issue is consistent across web browsers & the Volumio iOS app. I have attached a screenshot to illustrate. Basically when I select the Playback zone icon I see both players but the one I want to switch to has a broken image icon and when I select it the player hangs and never connects.
Thanks, Marc