First thing is that it is probably a ground wiring issue. Have you got ground connected between your FC, ESC's camera and vtx as you need to make sure they have a common ground.
If the above does not solve the issue could you share a video (on the bench if you dont want to go out and fly) of this issue and also some details on your setup along with pic, but it sounds like it might also be a power issue possibly so either your motors are drawing too much current, or causing too much interference somewhere. I will then pass the video onto the board designer and they should be able to help.
Also by testing this on the bench without any props that could also point towards the problem of motors drawing too much current maybe, as if it does not happen without any props.