Fedora, by default, does not include MP3 support for legal reasons
you need to install rpmfusion
su -c 'rpm -Uvh http://download1.rpmfusion.org/free/el/updates/testing/5/i386/rpmfusion-free-release-5-0.1.noarch.rpm http://download1.rpmfusion.org/nonfree/el/updates/testing/5/i386/rpmfusion-nonfree-release-5-0.1.noarch.rpm'or
su -c 'rpm -Uvh http://download1.rpmfusion.org/free/el/updates/testing/6/i386/rpmfusion-free-release-6-0.1.noarch.rpm http://download1.rpmfusion.org/nonfree/el/updates/testing/6/i386/rpmfusion-nonfree-release-6-0.1.noarch.rpm'
now go ahead and run the following commands
yum update @sound-and-video
install the xine version
yum install xine-lib-extras-freeworld
install the gstreamer version
yum install gstreamer-plugins-ugly
















