The 2nd generation Apple TV 4K supports HDMI ARC and eARC. The new feature lets you play audio from your TV, including connected devices like a game console, through HomePod speakers.

HDMI eARC support
The old Apple TV 4K supports 'Home Theater' mode, which allows you to wirelessly pair one or two HomePods for audio in up to Dolby Atmos. This works with audio from Apple TV; movies, games, menu sounds etc.

A new feature in the 2nd generation Apple TV 4K is support for HDMI eARC and ARC (Audio Return Channel). It allows Apple TV 4K to pull audio from the TV screen (must support HDMI ARC/eARC) and then beam it wirelessly to HomePod.

- "Apple TV will play audio from your television and its inputs through your home theater HomePod speakers. Use your television's 'passthrough' mode for best performance," explains Apple.


 HDMI ARC/eARC support in the 2nd generation Apple TV 4K

Game consoles, too
This includes audio from devices connected to the TV screen, says Apple. These could be devices like PlayStation, Xbox, set-top boxes, and Blu-ray players.

It works with the original – now discontinued – HomePod that must be set as the default speaker for Apple TV (make sure that both are added to the same room in the Home app). It does not work with the HomePod mini or AirPlay 2 speakers from partners. Bloomberg recently reported that Apple is working on a combined Apple TV box and HomePod speaker.

HDMI ARC/eARC support is currently in beta and is supported only on the 2nd generation Apple TV 4K, which launches today.

HDMI ARC/eARC on Apple TV – how it works
In Apple's words:

What you need
- Apple TV 4K (2nd generation)
- HomePod speakers*
- A TV that supports HDMI ARC or eARC
*HomePod mini speakers aren't supported.

Turn on HDMI ARC or eARC
- Set up your HomePod speaker or stereo pair as the default speaker for Apple TV.
- Go the Home screen on Apple TV and select Settings > Video and Audio > Default Audio Output. Under Default Audio Output, make sure that HomePod is selected. 
- Under Audio Return Channel (Beta), select Play Television Audio. You'll know ARC or eARC is turned on when it says On (ARC) or On (eARC).
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