Get external key

I get " failed to enable external key"
My card is decklink duo 2
My declink config:


What is the problem?

In the Decklink control panel applet set the output of channel 1 to SDI 1 & 2:

And then get rid of the line <key-device>2</key-device>. That should do it.

How about if i use older decklink card?
Like decklink studio 2?

If you don’t want fill+key output, then you can ignore this error. It tries to enable it by default, but it looks like your card doesnt support it.

Exactly i need it and I can’t have this

This card is very old and, if I remember right, can not do fill & key. But what is the problem? The Decklink Duo 2 is very cheap, why bother with older cards?

Yes you are right it doesn’t support key