Ad audio is set by media volume. While in-game sounds may be disabled, ad-audio may play if the ad is tapped and your device volume is enabled, (not on Vibrate/Silent mode.)
To adjust your media volume, press the Volume down button on the left side of your device. To completely disable sound, we recommend depressing the switch on the side of your Android device to enable Vibrate/Silent mode.
Android Support Article: Changing volume, sound & vibrate settings
Don't see what you're looking for? Let’s chat about it. Select Contact Us in the upper-right corner.