Audio problem: Lorraine comes to see Marty in Doc's garage in 1955 to ask him if he will go to the dance with her. Just before Lorraine moves to the other side of the car from where she walked in, she begins to say something to Marty. The problem is that her lips don't move when she talks, I guess the right clip ended up on the editing room floor. (01:11:40)
Audio problem: Just before Toby closes his bedroom door while Roy and Ronnie are arguing, if you listen carefully you can faintly hear director Steven Spielberg telling him to close the door. (01:05:00)
Audio problem: In the scene where the birds have a party, Pedro and Nico sing "I Wanna Party". If you look at his lips he sings "My life" but he just smiles.
Audio problem: When the rowers in the Roman galley were going normal speed, you could tell that the drum was sounding before the drummer hit it.
Audio problem: At the end of the movie when they sing "you are my sunshine" they movie into a L.S. and you can see that the words aren't synched in to their lips. (01:31:30)
Audio problem: The keyboard Kevin gets from the music shop seems to have an interesting trait, in that the high notes are on the left. This must either be bad "audio dubbing" or something to do with the shot perhaps being reversed, although I doubt this. It's most likely a post-production audio error as very very few keyboards or pianos are configured in this way.
Audio problem: In the end of the movie, when Ben is found by two Swedish backpackers, the subtitles doesn't match with what the the woman is saying. The subtitles say something like "Come on, lets get him out of here", when in fact she says "Herregud hur kom han hit?", which roughly translates as "Oh my god, how did he get here?"
Audio problem: After releasing the whaler prisoners aboard Acheron, Mr. Hogg shouts, "Now do your worst!" though his mouth clearly does not say that. (01:56:25)
Audio problem: The radar operator (making the sounds of a garbled intercom) is laughing through his next line "I'm having trouble with the radar, Sir." (After/when Dark Helmet throws the intercom across the control panel). (00:21:45)
Audio problem: When Abby, an elf, is about to tell Santa that Charlie is on the naughty list, she says something about 'Brazilian cocoa beans'. As this line is heard, you can see that her mouth is moving completely differently from the words we hear.
Audio problem: As Tim Robbins drives off at the start of the trip to California, he sings "The Age of Aquarius," but his lips through the car window aren't mouthing anything close to the line he is singing. (00:28:10)
Audio problem: When Tiresias describes Scylla to Odysseus he states, "She lurks in the shadows, hoping to fill her belly." However, when he says, "hoping to fill her belly," his lips don't match what he is saying.
Audio problem: When Nick is talking to his friend in the casino lobby, in a side view his friend says "...not one quarter..." but you can clearly see his mouth doesn't move. (00:11:30)
Audio problem: When Irina and Mutt are sword fighting in the jungle, the blade strikes all make echoing sounds.
Audio problem: When Sandy is underwater fixing the net, Kim places the rope in Flipper's mouth and says, "Bring this to Sandy," but her mouth is not in sync with those words.
Audio problem: When the spider is attacking Wicket, Cindel screams but we can see Cindel when she screams (left hand corner when Wicket is pushed onto the floor) and her mouth isn't moving.
Audio problem: When Happy is talking to Peter in the kitchen at the charity event, from the angle over Happy's shoulder he's talking but the side of his face isn't moving, from that angle we should see his chin move up and down.
Audio problem: When Gwen is getting hit on by the drunk guy who says "nice outfit", the lines for both drunks have been poorly dubbed over and don't match their mouths.
Audio problem: When Pikachu has coffee cups all over Harry's office, Tim starts knocking them over. The cups make a plastic/can sound, but the cups are cardboard.
Audio problem: Notice when anything heavy hits the bottom of the ocean it makes a loud thud. The bottom is soft sand and wouldn't make noise.