Control4 volume levels (grouped or single zones) not updating in Control4

I have a client with Devialet speakers in one room, Sonos in other zones. Zones are set as airplay and work perfectly, except:

When controlling volume in Roon, it doesn’t feed back to Control4 for zones. This means that Control4 always shows 0 as the level until you change it. Zones are set up as audio endpoint 2 for volume and endpoint.

Has anyone else seen this?