After you've set up your Chromecast, you can cast music to your TV with Google Play Music.
Cast music with your phone or tablet- Connect your device and Chromecast to the same wireless network.
- Open the Google Play Music app
.
- Touch the cast icon
.
- Select your Chromecast from the device list.
- Select a song, album, or playlist.
- Touch the play icon
.
.To disconnect: Touch the cast icon 
Playback controls: You can use the playback controls on the Google Play Music app or your device's notifications.
First, make sure you have Google Chrome 
Then, follow these steps:
- Open Chrome
.
- Connect your computer and Chromecast to the same wireless network.
- Go to Google Play Music (play.google.com/music) using Chrome.
- You can also add the Play Music chrome extension and cast from here instead.
- Click a song, album, or playlist.
- Click the play icon
- Near the bottom of the screen, click the cast icon
- Under "Connect to a device", select your Chromecast from the device list.
To disconnect: Near the top right of your browser, touch the cast icon
Playback controls: You can use the playback controls on Google Play Music, near the bottom of the screen.
Note: You may want to keep the music player open when casting music from your computer. Playback controls can't be used after the music player has been closed, the computer has been turned off, or an Internet connection has been lost.
On your phone or tablet
If you are having trouble casting your music or the cast icon is missing, try these troubleshooting steps.On your computer
Visit this page if you are missing the cast icon.If you are still having problems
You can contact our Chromecast support team.Note: During playback, you can turn the screen off on your device or computer to save battery. You can also use other apps on your device and open other tabs on your computer's browser while casting.