x box trouble

[concept3]

Ive asked everyone I can think of but no one can give me an answer, I was just reading bartmans post and It seems some of you know alot about x box so here goes. I just bought morrowind game of the year edition and im having problems with it, when I first put it in an select load game it takes about 20 minutes to load! and then when im finally in the game and try to talk to someone it takes about 5 min for the text to appear, and if i open a door 90 percent of the time it freezes and if it does let me through the door i have no sound. The guy at the store told me it might be a faulty disc so i traded it 3 times to no avail, i also went out and bought a cleaning disc with 4mm brush on it, nothing. My x box does not have a problem with any other game just morrowind. Can anybody give me some advice? Has anyone ever had this problem with a game? thx in advance