I have the same issue here. HDMI ARC as well as optical sound from TV to receiver results in no 5.1 sound.
If Netflix is steamed using the new Chromecast Ultra, 5.1 sound is working as expected.
Resetting the Chromecast Ultra to factory defaults like proposed in one comment did not help here ☹️
What can I do to make things work like expected with the Pro account?
any news on it? It it's really disappointing when a feature we have paid for is not working at all.
Is 5.1 surround sound with Chromecast working for anybody here?
Ok, good point, the tech related point of view.
@GraceFromGooglemaybe you could forward this thought.
I am QA for myself, and I run into some "conditions" I would have figured out before.
Of course, developing a product makes you blind on some places, but at least I would have checked 5.1 passthrough on the most common 20 TVs, and at least from every major company.
It does not make sense, to know, that Netflix runs with 5.1 and Dolby Vision on ChromeCast Ultra, but Stadia lacks color in HDR (Destiny2) and has only 2.0 passthrough.
To expect people to be able to have 5.1 PCM over eARC is also not a good point.
For me, I have a TV with HDMI 2.1 already, manufactured in August.
My Receiver (Yamaha RX-V685) has also eARC enabled already.
I list these points, as in your FAQ is mentioned, that it will work with 5.1 Sound when your TV supports eARC.
But it does not. Besides, only few TVs out there are supporting eARC.
This was a wrong approach from start. Go and broadcast Dolby Sound, and everyone will be fine.
Yes, also google because more paying customers will balance the more costs for Dolby Licences.
If Netflix can do DD+ in a 4K stream, I guess Google can, too.
BTW... I now recognize that ChromeCast Ultra was not able to broadcast Dolby Atmos, but my TV is? Interesting.... Tested with 2nd season of Punisher. My TV played with Dolby Vision and Dolby Atmos, but Chromecast only showed DD+ in my receiver and no DD+/ATMOS. Might be a hardware issue.
Anyway: @Amphoterism is right: If casual users will struggle here, thers a huge #**bleep**storm incoming!