I am trying to find a solution for an existing set up. I have my TV in a separate room from my components. An HDMI cable runs from an Onkyo TX-NR656 receiver to my TV. All components are connected to my receiver (Apple TV, Turntable, Satellite Box, etc), so the receiver is the main audio/video control switch. All controlled by Logitech IR remote with IR extender. I want to buy and use a Sonos Playbar, but I am not sure how to get audio stream from all the different inputs to flow from the TV (connected via the main HDMI) to the Soundbar. Is it possible?
If your receiver is passing audio through the HDMI cable going to the TV then you could connect the playbar, as intended, directly to the TV optical audio output. You could also use an HDMI audio extractor but I don't know if there is any advantage doing it that way You would mute or turn the receiver volume down when you wanted the Playbar.
If it doesn't pass audio through to the TV then you might be able to use the zone 2 out of the receiver with an analog to digital converter if the receiver sends audio from digital and HDMI inputs to zone 2. Many don't. If you use a Denon Heos soundbar that has analog input so you wouldn't need the ADC.
You won't be able to use the Playbar as your front three speakers or center. You would not want to use it at the same time as your surround system. It would just confuse things