This article explains how to use an Apple TV with a Sonos Playbar. Instructions apply to the fourth generation Apple TV or Apple TV 4K and the Sonos Playbar or a Sonos Arc soundbar.
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If you want to use your Apple TV with your Sonos Playbar or Sonos Arc, you’ll need to connect the systems through your TV, as the fourth-generation Apple TV and Apple TV 4K don’t have optical audio outputs. Here’s how it works.
Connect Apple TV to an HDTV with an HDMI cable.
Download and launch the Sonos Controller app on your iPhone and open Settings.