Audio problem: When the CT technician asks John if he'd like some help getting down, John says "Thank you very much", but you can tell that he's not saying anything and that the line is just dubbed in. (True, the camera is facing away from him, but his jaw and face aren't moving at all.)
Audio problem: When Sam is talking to Ghostface for the first time, as Ghostface says the words "I'm going to show the world who you really are," the camera cuts to a different angle. If you watch Sam's chin at the top of the screen, you can blatantly tell that she's speaking, but no audio is heard.