Whether you have a single, original HomePod or use a couple of them for stereo sound, you can hook them up to your Apple TV 4K. This ensures the TV device will always make use of the HomePod when you’re enjoying movies, TV shows and music. You won’t need to keep changing the settings to immerse yourself in Dolby Atmos, Dolby Digital 7.1 or Dolby Digital 5.1 surround sound.
The feature, introduced with iOS 14.2 and tvOS 14.2, entails using the Home app first to put the HomePod and Apple TV 4K in the same HomeKit Room. Also note this won’t work with Apple TV HD and you can’t set HomePod minis as default speakers either. For those, you’ll need to use AirPlay and remember to switch to them each time you fire up some content on your Apple TV.