I want to use the playback. (DeckLink 4K Extreme 12G)

I want to output video to playback using the API you provided.
I try DeckLink SDI 4K model, the playback output will be succeed.
But with DeckLink 4K Extreme 12G model, the playback output is not.
I connected to the monitor (Blackmagic Video Assist) using SDI.
DeckLink SDI 4K models have one output port and DeckLink 12G models have two output ports.
Is it not working because of the difference?
Is there a way to set up DeckLink 12G models?
please answer about my question.
Thank you.

Hi Lee, It sounds like you are using the Decklink API. I think you are better off asking this question in the Software Developers forum. See the link below.

viewforum.php?f=12