Using camlink to capture camera but black screen

hello, I’m new to unreal and learning about virtual production. I’m facing a problem that the media player show a black screen after I selected the capture card input, I want the camera signal can be input into unreal to composite with my virtual environment. My setup is a sony a7 camera link to my pc with a elgato camlink 4k.
But I can’t find any tutorial talk about there is a issue of camera connection. Dose anyone had a similar experience and know the solution? thanks.

I have the same problem. Any luck finding a solution? Would appreciate it if you could help.

Have you solved this problem yet?
What version of Unreal engine are you using?
I managed to get it working with my camera but only in UE4. My camera is a sony pxw-fs5.