hi,
on small displays the playback-tab cant show all infos. Especially The multiroom-device bar has to been scrolled up to see which device is currently shown on display because there is no other identify info about the active shown device.
suggestion:
If changing the multiroom-device the background-image of the selected device (of its own) should be changed too. So there can see simple which device is actively displayed to operate - or put a simple info of the currently shown active device e.g. left from the congiration-icon in the top bar.