Summary - Apple TV using HomePods isn’t worth the effort, until key issues are fixed approach with caution, you milage might vary
My Bose 3-2-1 surround sound system is on it’s last legs (keeps turning off), so I was thinking I might try to use a stereo pair of HomePods as a temporary solution until I can put in the research and in store time to choose a new solution (currently thinking Bose 700 or Samsun Q90R).
Sadly this little experiment has failed, for the same reasons as everyone else, however I wanted to capture the key details to help others from trying to go down this path (at least as of today with HomePod v 13.4).
The good
Stereo pairing works quite well, volume levels with music great
Control from Home to setup wasn’t too bad at all, a little fussy, but ok
Single Siri Remote and iOS remote app for everything, including volume
I didn’t notice any delays in lip sync or major performance issues (Channels, Plex, Apple TV, Netflix, Stan)
The bad (and these are deal breakers IMHO)
Plex and YouTube don’t reliably continue to play audio after Apple TV wakes up and you try to play something (reported elsewhere also).
The Apple TV when returning from extended sleep or re-boot often requires you to reselect the HomePods as the sound output, it seems to really want to default to HDMI (obviously really need HDMI for Video to TV)
At low volumes sound is unbalanced between left and right HomePod, each volume increment up you can head the sound different change from left, then right, then left (very odd)
Configuration
Apple TV 4K static IP address connected via 5.0 GHz AC (dedicated to Apple TV and HomePods)
2 x Space Grey Apple HomePods, configured as stereo pair, static IP addresses & connected to the above mentioned dedicated network. (I also tried a single HomePod and had the same issue as above)