Only one out of 3 Sonos speakers is discovered

Configuration
1

I have 3 Sonos devices (2x ikea sonos speakers + sonos beam).
I grouped them together in the Sonos app as a 5.0 surround system.

When I set up the integration via the home assistant UI, only the Sonos Beam is discovered. (1 device 1 entity).
When I play something, say via tts, all 3 speakers are playing so it appears that home assistant considers that all 3 speakers are one entity.

Is this because I have them grouped in the Sonos app or am I missing something?

2

It is because they are grouped. If you go through the Sonos App, it treats them as a single entity when you play audio or change volume.