This thread is like a mixture of a conversation and a question.
I recently bought the new Sonos Beam, and started experimenting with surround sound. And before you go out and buy one; if you use a PC to game through your TV - you might have a problem.
Now, the issue is you can't get Dolby Digital surround sound from using an Nvidia GPU (AMD, I am not sure). You're strictly locked to stereo, unless you have an Nvidia Quadro GPU or a very unique TV. But, chances are you don't as Quadro's cost multiple thousands of pounds and all the TV's I know supplement the issue.
So, what platforms pass in delivering Dolby Digital surround sound?
Blu-ray player: PASS
TV built in apps: PASS
PC gaming with Nvidia GPU: FAIL
So, I plugged the HDMI in from my PC (GTX 1080Ti) to the TV (Sony 43" XE7073). Then, the TV will re-route the signal to the Beam. And there is nothing wrong with any of the hardware from the PC to the speakers in delivering 5.1 Dolby Digital surround sound. So what's the issue?
Cut short, every TV has what we call an EDID which informs the player (in this case, GPU) about what video and audio signals to send to the monitor/TV. Now, the TV, Sonos Beam and PC all have the capable hardware to deliver 5.1DD... but the cause of the issue is the TV and Nvidia.
Firstly, TV's have built in stereo speakers, which means the EDID passed will inform the GPU in your PC that the HDMI sound should be in stereo. And Nvidia give you NO option to override the EDID to pass 5.1DD like the Xbox or PS4...
So, I am stuck with stereo sound with PC gaming 'til Nvidia gives you the option to override the EDID.
It might work if I plug the HDMI from my GPU to the TV, then another cable from the optical output (optical to HDMI adapter) into the Beam for the audio. Unfortunately, that completely ruins the simplicity of my Sonos system and that's the last thing I want to do!
Anyway, I am fine with the setup so far - actually heavily thrilled! I love listening to music, watching films and YouTube through it (5 stars from me)! But, I will leave this thread open as a question if anyone has a technical solution to this problem. I like my PC gaming, you see. If I am stuck with stereo, it's not the end of the world.