First note that the video takes up to 30 seconds to display.
Audio begins playing much sooner.
There are 2 common reasons you are hearing audio but cannot see video. Your version of the Windows Media Player does not have the newest video decoding components. You will be prompted to allow these to be installed. These downloads are very small and will take only a couple minutes on a 56K connection. If after the download completes you cannot see video, close the media player and click the link on the web site again.