There are two ways to use Google Mini Deezer at present is the only app supporting it’s use and is a paid for product to work within the google range of products. You can however create a home group in your google app ans cast to your group, details below for both solutions.
For Deezer to work you must have a Premium Account which is subscription based.
Here are the instructions for Deezer:-
How to add CAMBRIAN RADIO to your google device.
You can add CAMBRIAN RADIO into your Google device (Mini) manually using the steps below.
PLEASE REMEMBER:- You must have a Deezer premium account for this to work.
Setting Deezer up on Google Home Make sure your Google Home device is set up and that you’ve downloaded the Google Home app from the Play Store.
FOLLOW THE STEPS BELOW
1. Open the Google Home app and go to the Home tab
2. Select the Add icon located in the middle of the screen
3. Select Music and audio located under the Manage Services section
4. Choose Deezer by selecting the Link icon
5. Confirm LINK ACCOUNT
6. Enter your login details If you have a Deezer Family account, you’ll be asked to select your Member profile
TO CAST TO YOUR DEVICES :-
Open your Google App on your chosen device and create a group named something such as Home Group, Streaming Group etc. Add the devices you wish to cast to, to the newly formed group. (To cast to all the group all the devices must be in the same wi-fi network to work.)
Once completed open a chrome browser on your PC. ensure you are logged into your google account.
In the Chrome browser navigate to this URL:- https://securestreams3.autopo.st:1430/;stream.mp3
When the music starts playing, go to the three dots to the right of the browser address bar, click it and select the CAST option and cast to your newly created group. the music should stop on your PC and now be casting to your group devices.
For more info, search google for more on Casting to nest devices.