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Sucks, sound quality unacceptable... these are all arbitrary, it's hard for us to troubleshoot things like that. But it's possible that you're using a wrong driver for your soundcard. Post up the following:
As root, open up a terminal and type:
And post up what you get, then type:
And post that up. To copy and paste from a terminal all you have to do is highlight the text, and then using your middle button on your mouse, place the cursor in this reply box and click the middle button. Highlight and paste. If you don't have a middle button (scroll is a middle button), use both mouse buttons at the same time.
Also, you are using a music player to watch movies, not the greatest idea. You might consider using something like mplayer. However, be aware it's a daunting task for a newbie, take your time and don't get frustrated. There are hundreds of threads on it here that'll help you figure out how to get it installed.
The search button is located in the upper right hand corner of the screen.