Please check out your device media volume.

■ How to check out media device volume

1. Press your device volume buttons

2. Check out the volume settings

If your device volume settings are properly set, please check the sound option at the Settings in the game.

■ How to check out system settings

1. Select the Admiral portrait at the left-upper of your game screen.

2. Select the Gear icon.

3. Select  [Manage System] > [Sound] > Change sound settings of  [BGM/SFX/AMBIENT]