The thing is, it didn't stop... If it hangs, all I have to do is restart the console and I'll be able to start the game again. I never got any reading errors of any sort, so that's why I think the problem isn't the optical unit. It just makes a horrible loud noise and, at first, I even thought it was scratching my disk, but it wasn't (what I noticed is that the middle of the CD is scratched, but everywhere else is just fine).