A short clip I generated in Windows Media 9 seems to play fine on most PCs. On on system a viewer reported the sound was ok but she saw a kaleidoscope of colors...no image. What could have happened?

I generated a Realplayer version. It plays on my system with sound but no image. What could be wrong? The realmedia 9 450k video template was used.

Quicktime is ok on my system but I haven't distributed it yet.

Thanks,

David