Audio problem: In the poker scene, when Jack picks up a card from the deck, it makes a very loud and long noise. Much louder and longer than the movement of the card against the deck would justify. (00:23:15)
Audio problem: After Jack asks Rose "do you love the guy or not?" the camera shows him from behind, and he is moving his jaw as if he is asking the question again. (00:47:30)
Audio problem: When the one lookout says "b*****ks", his mouth doesn't match what he is saying. (01:31:20)
Audio problem: When the steward is getting Rose and Cal's life jackets from the closet he says about top coats and hats, However his mouth stops moving after the word coats. (01:44:00)
Audio problem: When Rose is talking to Thomas Andrews, telling him to tell her the truth about what has happened, listen to the voices in the background. At one point in the scene you can hear someone saying "Yes madam, please put it on immediately", then someone laughs. Right at the end of the scene, the same line can be heard in exactly the same tone of voice, followed by the laugh - it's obviously a loop. Although some tracks in the mix of the soundtrack do not loop at that moment, the track with the mentioned sentence does. (01:47:30)
Audio problem: When the leader of the orchestra suggest to play "Orpheus", the music starts later than the musicians actually begin playing their instruments. (02:07:00)
Audio problem: When the Captain is watching the overturned boat trying to be launched, there is a crew member working on the davit, causing it to make a rapid clicking noise. But soon after the noise stops, the crewmember is still turning. (02:29:15)
Chosen answer: During the several years it took to construct the ship probably, or in any of the supplies/food brought on board, or in the furniture brought on board. A single pregnant female rat can be responsible for thousands of rats in a very short space of time (the offspring are not too choosy about who they breed with).
Soylent Purple
A pregnant female rat could have made a home in a underneath a third class couch and had the other rats then all the females would have baby rats quickly.