same here - until yesterday everything worked well with the sonos and homey system.
Today I receive the “error resource gone” issue when I try to control the sonos speakers…
When I change the volume via the sonos app (outside homey) I can see in realtime volume changes of the sonos speakers inside the homey system.
I will contact athom…
Addition:
I powered of ALL sonos speakers and powered them on again…
Now it is working again 
