Audio problem: When Jack tells the bad guy he wants to get off the bus, he says "it's not against the rules." The bad guy then says "All right, but I want you back real fast." Look at his mouth while he says the line. You can see that the talking isn't similar to the moving mouth. This is because Dennis Hopper originally said "in ten minutes" instead of "real fast." Since Jack was gone longer than 10 minutes, the line was re-dubbed to something less specific. (01:10:37)
Audio problem: When the first bus blows up (the one that Bob was driving) you can hear the explosion before the bus actually blows up.