Hi all, I'm experiencing the following problem, which I also had in beta. The mission videos frequently suffer from extreme stuttering, enough that they become unintelligible. This typically happens a few seconds into the video, and persists until the end of the video. After the video is completed with stuttering, I can push "replay video"; if I do so, the video plays correctly. I have a gut feeling that this is related to low network bandwidth.
It does sound like bandwidth issue, since replay works. Try increasing the Video Buffering to 75% within settings. If issue still persist, try 100%.