If you have more than one Google Home device, it's easy to pair the speakers to play audio from all devices at once. Here's how to set up multiroom audio on Google Home.
How to set up a Google Home group
If you have not yet set up a Home group launch the Google Home app, tap + Add and select Create speaker group. Select the speakers you wish to include (these must be on the same Wi-Fi network as your phone or tablet), give it a name and save the group.
If you have already set up a Home group but want to add new speakers to it, launch the Home app, select the icon for the speaker you wish to add, then tap the cog wheel icon to enter the device settings. Scroll down to and select Groups, then assign it to your existing Home group and press Save.
To play audio on a single speaker you speak the usual command. But to play audio on all speakers simply say "Okay Google, pay [song name] on Home group."
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