Note: if you hit the reverse button, it flips your clip from its i/o points. If you give the clip a speed of -100, the clip is flipped over its starting point.
I think I know every feature of 3. Bring it on, 4!
RE Music: I'm not sure if this is what you are hearing or not, but whenever I import music from a CD I usually have to drop it down 10-15 db because it comes in too hot (loud).
RE RT: The faster your machine the more RT FX you have.
Wano: I'm gonna guess you're trying to just drop a mp3 into your project and it sounds bad. If so, you need to export it to an AIFF file and then import it in FCP3. It's a stupid bug.