The keyframe interval decides how fast a viewer sees the first frame. With a keyframe only every 2 seconds, viewers waited 0.7 to 2.4 seconds longer for the picture in our measurements. A keyframe every second keeps the start short.
Settings per encoder
OBS
Every value in the OBS output settings, step by step.
Kiloview E1
The H.264 main stream parameters in the web interface.
Blackmagic WebPresenter and ATEM
A streaming XML with bitrate profiles to load into the setup utility.