If you can't hear audio in the mobile app, please check the following:

1. Make sure your mobile device is not in silent mode.

2. Make sure your mobile device's speaker is working properly, and that the volume level is turned up.

3. Press the ""i"" button in the Live View screen to check your camera stream's current status. If ""Audio stream"" is marked as ""Waitng"", please wait until it changes to ""ON"".

4. Please note that the DNR-322L does not currently support audio streaming.