This is something a lot of us have wanted for a long time. Now I’m not sure if this was a change in Plex, or a feature developed from Amazon, but either way it works now. Albeit with limitations.
Now you can’t use the traditional syntax of “…play music on [speaker group]”.
With that said, under your device Groups, you have the option of setting a preferred speaker for your group. For your preferred speaker, you want to choose one of your multi-room speaker setups. So for example, in my Kitchen group, I have the preferred speaker set to play on my first floor speaker group which includes 3 other Echos on the first floor. So when I tell Plex to play music from my kitchen Echo, it plays on all 3 Echos on my first floor multi room music group.
It seems to work pretty well. Another limitation is that you can’t skip tracks from any other Echo than where you started the command, but that’s not a big deal for me.
Pretty much haven’t used my Echo Dot stereo pair/Echo Sub, bought for the bedroom a couple of years ago as this was missing. Due to all this Covid-19 isolation and working from home, and wanting some tunes, figured I’d do a quick search to see if it is fixed and came across your post.
Had to delete and re-add the sub and setup the group again and the preferred speaker and after a little typical perseverence, it works!!
Great sound for a small room, at last, from pretty much hidden speakers!
Many thanks for taking the time to post this…very useful.
Now, if there was a was to select tracks from the PLEX UI on a phone or other device and have it play to the Alexa Speakers in stereo! I know…greedy…
this is great info, thanks. I’d found that starting Alexa on a multiroom group and then immediately asking Plex to play something allowed Plex to play multiroom but this is much better solution.