Your device must have Android version 4.4.2 or higher, and have location services enabled.
Make sure “Power Saving Mode” is off on your device and the “microphone” permission in the Google Play Services app is turned on.
To turn on microphone permissions for to settings > Apps > Google Play Services > Permissions. Look for “Microphone” and slide the slider on.
Make sure your device is connected to the same Wi-Fi network as your Chromecast.
Open the Google Home. Note: This may also be called “Home.”
In the top left corner of the app’s Home screen, tap menu > Cast Screen/Audio > Cast Screen/Audio.
Select your Chromecast.