When joining a live event in teams the desktop application will sometimes show a black screen and the user will need to leave the event and re-join. It may take a few tries for the user for the video to successfully load in teams. It may also load on the first try. It appears random. This behavior is the same on both the Mac, Windows, and web clients. If the user joins from their mobile device (iOS and Android), the video loads every time. A user can also load the stream successfully every time in stream or yammer. It is only when accessing it through the Teams Desktop Application/Web that they experience a black screen.
We are leveraging the External Encoder support and using OBS to send the video feed to Stream.