The BMD Blackmagic Design DeckLink Duo 2, BMD DeckLink Quad 2 and the BMD DeckLink 8K Pro video devices require correct Connector Mapping Settings, in order to provide all available inputs (four or eight) for to the just:in mac engine. Please open the macOS System Preferences and open the Blackmagic Desktop Video Preference Pane.
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There you can see your connected BMD Blackmagic Design video devices. Click on the button in the middle of the screen to open the device settings.
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