I have several google home MINI's (1st gen) as well as chromecast devices consisting of Nvidia Shield 2019 pro.
Using the google home app on my android phone I have created a speaker group consisting of 2 google home minis.
When I audio mirror (from my phone) to this endpoint I hear audio fine and in sync on both google home minis.
Now, if I introduce my nvidia shield to the group it doesn't work as expected anymore.
The group now consists of 1 nvidia shield (identified as 'Android TV') as well as the 2 previous google home minis.
When I use audio mirroring from my phone onto this group I get audio rendered on the nvidia shield only.
The 2 google home mini's also in the group are absent of any audio.
I guess the culprit here is the fact that the builtin chromecast of the nvidia shield is seen as a chromecast with video renderer capabilities (android TV) and this takes presedence over audio only devices.
It would be nice to have my nvidia shield work as an audio only chromecast as it often being used without the TV turned on. It's connected to a highend HDMI AVR (amplifier).
I do not yet own any chromecast 3rd gen. devices, but I guess it would be the same issue.
For reference the same group works fine when casting from spotify. The audio is heard across both the google home mini's as well as the nvidia shield and in perfect sync.
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