I had this problem too in Ubuntu 12.04. So, I removed mplayer2 and installed mplayer:
sudo apt-get purge mplayer2 sudo apt-get install gecko-mediaplayer
I had this problem too in Ubuntu 12.04. So, I removed mplayer2 and installed mplayer:
sudo apt-get purge mplayer2
sudo apt-get install gecko-mediaplayer