No audio is present or it is not clear

1.    Unplug the power cable for 30 seconds and plug it back in.

2.    Make sure the volume level is sufficiently high on your receiver and TV. Press the MUTE/VOLUME button on your receiver’s Remote Control Unit or TV set’s Remote Control Unit to turn the volume up.

3.    Try to select another channel and go back to the original one.

4.    Check the connection cables between the receiver and the TV set or Hi-Fi.

5.    Check, if you have switched the Dolby Digital Receiver option ON in the LANGUAGE OPTIONS screen, but your external digital surround sound receiver is switched off.

6.    Try to restore default settings:
Menu> Installation> Factory Reset> Yes.

7.    Test audio on a different device.