If there is no sound emitting from your IOS device, first please check that the volume is turned up on the device.
Next, please check the switch near the volume button on your device to make sure your device is not muted.
If neither of those options have resolved the issue, please follow the steps below:
1. Exit Sono Flex
2. Open the Settings app
3. Select General on the left side of the screen
4. Select Mute on the right side of the screen
5. Select Lock Rotation on the right side of the screen.
6. Close the Settings app and re-open the Sono Flex app.