You mean, you already have items in the zone's Playing Now, and try to start them from there? What's in a Zone, Stays in a Zone.
I have an album queued up in the Audio Zone, and videos queued up in the Video Zone. (P.S. is there any way to stop MC from adding
every single video in the view to a playlist when I double-click a file, without stopping it from adding the whole album if I double click an audio track?)
If the album is currently playing through the Audio Zone, if I click on the Video Zone and then start playing any of them (by double-clicking) MC tries to play the video, but
doesn't stop playing the music, which means the device is in use and video playback stops with the "Playback could not be started on the selected audio output" error. (I use WASAPI Event Style with exclusive access)
Similarly, if I have a video playing in the Video Zone, click on the Audio Zone and then start to play a track I get the same error, because it's not stopping the video playback first.
If I start playback from anywhere else in MC18, switching works as expected. But this is no use to me, because it means I lose the "Playing Now" playlist, which is the whole reason for setting up these multiple zones.
The exception is if I use the Overview "zone", which keeps the "Playing Now" playlist visible
and switches between zones correctly - but it displays all my DLNA devices too (which I don't want) and doesn't let you customize the view.