Hi @jonnyjw.

Welcome, thank you for reaching out to Sonos Community since you already tried some troubleshooting steps let me try to assist you.

Yes, you can group all of your speakers as long as they are under the same Sonos application.

This will show you how Group and ungroup rooms.

If you need help with any other information, please be sure to let us know.

Because of the Play:5, (Gen 1) you would need to either have a split system or run everything on the S1 App.  It would group with the Play:1 with either set-up but the Play:5 wouldn’t be able to Group with the Beam in a Split System. Please see this article.

Edit:

Here is the information on a split system.

Edit 2:

Please see additional text in bold italics, for clarity.

Thanks - so if I understand this correctly I can group a Beam with the Play:1 with either the Sonos S2 app or the Sonos S1 Controller app? And the Play:5 (Gen 1) cannot be grouped to the Beam at all? 

If you're willing to accept the restrictions of staying on the S1 App, you can group all three. But you won't get the functionality improvements associated with S2.