Apple TV/HomePod sync
Why does my home pod play music randomly when trying to sync to Apple TV to watch television
Question marked as
The article you've linked from, Set up Wireless Audio Sync with Apple TV - Apple Support, details a process that attempts to improve lip syncing when watching video on your Apple TV with the audio routed to HomePod. To watch video with the audio routed to HomePod see Stream audio from your Apple TV with AirPlay.
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