Man, I thought it was my system only, I just deleted my files and everything! I have been having the same problems as all of you. I have choppy dialogue, fx sounds going away after a while of playing, but I also have some stuff different than all of yours. I cannot talk with Bastilla, Jolee and Carth when it says that they are disturbed about something or if it looks like they want to talk. This also means I can't do the Carth's son sidequest on Korriban, which I missed the first time around. The sonic nullifiers (or whatever they're called) don't work so I can't kill those firaxa fish underwater at Manaan which then keeps me from getting to the star map. I can run through doorways which are supposed to lead somewhere but I don't transit to the next area. I have a slight difference to the Leviathan though, my screen goes black after Carth and I run to the ship, at first I thought it was just loading but then I pressed start and the start screen came up. I saved and restarted and the screen wasn't black anymore it turns out that I was running around the hanger where the Ebon Hawk was on the Leviathan. I'm pretty sure I wasn't supposed to be though because there was no entrance to get onto the Ebon Hawk and I was walking through all of the objects on the hanger. I seriously hope this gets fixed somehow!