The reason for the black screen is because of the "Video Acceleration Function (Overlay output)".
To solve the problem, please see the below.
1. Start Bandicam before the recording target programs.
While the Bandicam program is running, the Bandicam program shuts off the overlay output.
Bandicam is running, the streaming videos will not be played through the overlay output.
2. Windows Media player can show the black screen when playing the recorded video.
Try VLC Media Player:
http://www.videolan.org/vlc/ (Recommended)
For more information, visit
http://www.bandicam.com/faqs/black_scre ... o_problem/