Video not shown to screen

[callw...@gmail.com]

Hi all,

I am working on a video display project and using gecko-mediaplayer, gnome-mplayer and firefox.
I found that sometimes the video is not shown, but the gecko-mediaplayer and gnome-mplayer is running at the background properly.

P.S.
I am using mplayer-vaapi v1.1.1, gnome-mplayer v.1.0.9b, gecko-mediaplayer v.1.0.9b and Firefox 24.0 on Ubuntu 12.04.3 LTS.

Any clues?

Thanks,
Wilson