The DCO-1781 is a 4 AES change-over. The switch is performed electronically by an internal router. In the event of a power failure, the signal is protected by the relays fitted on the rear module, maintaining the integrity of the selected signal at the output. The DCO card allows switching as a regular router, or alternatively the module can perform an audio silent switch between sources using the silent switch software option. Input selection can be performed manually or automatically.