1. Confirm if the volume is not muted from the control4 system.

2. Confirm that all audio systems are powered ON. i.e. Audio Matrix Switch, Amplifiers and DSPs.

3. Confirm if sound can be gotten from other video sources or audio source. i.e. Second DSTV, AppleTV, Kaleidescape etc.

4. If no sound from other video and/or audio sources, request a power cycle of the AV system by power cycling the power conditioner. 

5. If issue remains unresolved, escalate to technical support team.

These step also apply to other video sources.