TryOut Sourceforge
I don't know if you still need this help, but I encountered a problem playing videos on my VEOH media player(& WMP).
It gave me a FMP4 codec message. On the link above
"click" download. Then
click run. You will be given options, on what you want to download. The download corrected the problem my movie player works fine.
My problem was just like yours, sound NO Picture, weird yes, well I just selected all the options given when they were presented. The program will re=write any "older version" so no worries.
I hope this helps you.