I have the latest versions of both the Elgato Software and OBS. I am running on a Mac OS Sierra 10.12.1 , and I haven't found an answer on how to fix this for MAC. I have tried completely uninstalling both applications, and still the only thing that popped up was my webcam built in to my laptop. I make sure the Elgato software is closed and it still won't pop up. The Elgato works perfectly with it's own software and I can see the video, but on OBS I can't. I was hoping someone could help me!! Thank you!