Sometimes, two black bars will appear around the video during playback.
These bars are the player’s method to fit the video stream into the player. This happens whenever the player is embedded at a different resolution, than the one from the video’s streams.
For example, if a provider is encoding his streams at 640x360 px, and he embeds the player at 640x480 px.
HOW TO RESOLVE
Change or update your player size to match the video encodings.
If you need to use the current player size, please contact your account manager in order to change discuss an encoding profile change.