Comment 5 for bug 892333

Well I got this problem too. Just installed a fresh 12.04 and it worked ok. Then I did a few installs including enabling all this

non-free-codecs libxine1-ffmpeg gxine mencoder flac faac faad sox ffmpeg2theora libmpeg2-4 uudeview libmpeg3-1 mpeg3-utils mpegdemux liba52-dev mpeg2dec vorbis-tools id3v2 mpg321 mpg123 libflac++6 ffmpeg totem-mozilla icedax tagtool easytag id3tool lame nautilus-script-audio-convert libmad0 libjpeg-progs libdvdcss2 w32codecs libavcodec53 libavutil51 ubuntu-restricted-extras app-install-data-medibuntu apport-hooks-medibuntu

and now it won play, not even at a second try. Unisntalled (Completly remove) and re-installed with no sucess. Maybe one of the things I installed broke it.