Audio problem: When the professor is walking out toward the car after Bobby yells at his house, Bobby says, "You're joking with me," but if you watch his mouth, you can tell that he really said, "You're f - -ing with me." The original line was probably cut during editing to keep the PG-13 rating, but it's still a problem.
Audio problem: In the beginning, Estevez carelessly chucks an emptied trash can off camera and it never makes a sound to signify that it landed.
Audio problem: When Junior picks up the cat and it starts to hiss you can see that the cat's mouth isn't moving.
Audio problem: When the angry cab driver is yelling at the female cop that stole his taxi, the words you can hear him saying do not match is mouth.
Audio problem: Right after the doctor falls in the basement he is talking about how no spiders are going to be there. Then he keeps repeating "Oh s***" but it looks like his lips are delayed.
Audio problem: When Rocky steps down from the plane from Russia he says "Where's the kid?" but his mouth is not in sync. The scene was obviously dubbed.
Audio problem: When the members of the Dallas crew arrive on the Red October, Ramius asks Ryan "You speak Russian?" He asks the question in Russian, but his mouth is very visibly asking the question in English.
Audio problem: In the scene were Mel and Goldie are in the salon, and she says "I called him sick", you can see that her lip movements are totally wrong. It appears this line was changed as her actual words appear to be "I called him a prick," which is why the flamboyantly gay hairdresser replies with "Oh he is a prick" with such an implying tone.
Audio problem: This problem exists in the extended Director's Cut. When Narcisse is first introduced in the hospital, when we cut outside to Decker and the police walking to the room, they suddenly hear Narcisse grunting which makes them rush to his room. However, they are quite the distance from his room, and Narcisse's grunts are fairly low, so it's obvious they shouldn't have heard him from that distance. The audio mixing tries to make his grunts sound louder, but it doesn't sound right at all... they're way down the hall from the room, but his low grunts sound like they're coming directly right next to them. This is all the more confusing, as in the theatrical edition, they are alerted to a distant scream by a nurse, which was much more believable. (As the Director's Cut is currently the most readily-available version of the film on Blu-Ray online, and is the director's intended edition, I believe it should count as a mistake).
Audio problem: More than once in the piano playing scenes there's music playing even as the characters' fingers aren't touching the keys.
Audio problem: Three quarters into the movie, the girls have some wine, and little Kate overindulges. In the next take we hear belching and hiccups that don't match the girls sitting quietly on the porch swing, talking.
Audio problem: When Reggie threatens the man outside his club, Reggie's boyfriend runs at him shouting "You stupid bastard..." and he is restrained by the gang. His lips never actually say these words.
Audio problem: When Sharon curses Steve Rogers when he leaves her stranded in Rome she says, "Damn, jerk!", but her lip movements don't match the words.
Audio problem: In the final scene where Scrooge chases Dijon out of his money bin, Scrooge shouts, "I'll change your face, you thief," but his mouth isn't even open. (01:09:10)