NEC PA721X User Manual page 121

RGB/COMPONENT . RGB and component signals are identified automatically.
VIDEO .................... This switches to the video signal.
[SEAMLESS SWITCHING]
[COLOR SYSTEM]
[DIGITAL AUDIO SELECT]
HDMI ..................... HDMI: Selects the HDMI input connector's digital audio.
COMPUTER2: Selects the COMPUTER2 audio input connector.
DisplayPort ............ DisplayPort: Selects the DisplayPort input connector's digital audio.
COMPUTER2: Selects the COMPUTER2 audio input connector.
5. Using On-Screen Menu
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