yes it support sound and video but does not come with a player.
Download and install mplayer http://www.mplayerhq.hu/homepage/design7/news.html
That will solve you mp3 and video problems.
However this sounds like Redhat is not communicating with your sound hardware.
Have you run the Soundcard detection wizard in settings?
When I installed Redhat the sound was very quiet and I had to get an external amplifier to boost the sound. Is that the problem.
The other option is to install the superior ALSA drivers over you current OOS ones. They work well but are a pain in the arse to get working.