Check to  be sure all are on the latest update.

So, you have two Sonos ‘rooms’, both showing up in your controller, with each set up with a stereo pair of speakers, and you’re unable to ‘group’ them?

Which version of the Sonos OS are these speakers running? What network setup are you running? Is there any error showing when you try to group them? Can you play the same source on one room, stop it, and then play the same source in the second room? 

Hi Bruce. Thanks for your quick reply. I’m not trying to group them (lol not sure how!). I just have the two sets listed as different “rooms”. I can play my “living room” set but when I try to also play on my “family room” set, nothing happens. Also if I try to only play in the family room set. So bottom line is it works find on my Sonos One set in my living room…but can’t seem to get any sound from my Sonos Play:1 set in my family room. 

For how to group, click on the underlined word in my reply. I ‘think’, based on your comments in your original post, that you’re doing it right, but it doesn’t hurt to be sure. 
 

More troubling is your inability to play anything at all on the PLAY:1s. Beyond ​@Stanley_4 ‘s excellent point of making sure they’re running the same software, I’d be worried as to why they’re showing up in your controller app, but you’re unable to play anything music on them. I think at this point, I’d recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

There are a score of reasons that might be causing this, the solution mentioned is the easy one. 

Thanks Bruce!