Become Super User open up a terminal and add the proper plug in to play MP3s. Not enabled by defualt due to laws. Also do not trust what the RedHat/Fedora OS picks for you enter the list and choose the card yourself then go out and seek the proper drivers.
To play MP3s
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yum install gstreamer-plugins-mp3
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if Yum isn't installed take the steps to do so. Become super user and open a terminal.
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cd /etc
mv -f yum.conf yum.conf.bak
wget
http://www.fedorafaq.org/samples/yum.conf
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then
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rpm -Uvh
http://www.fedorafaq.org/yum
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