Audio problem: In the secret room where Hoskins and Dolores are hiding Roger right before Hoskins hits his head on the lamp he says, "crazy tunes," but his mouth doesn't move. (00:44:25)
Audio problem: In one scene where Jackson is caught by some bad guys you can see (and hear) that a couple of times when Jackson laughs it is badly dubbed over.
Audio problem: Right at the scene where Reggie Jackson points the gun at the Queen, Drebin fires a shot off at him from his watch. It goes astray, hitting some fat lady, and we hear him saying "whoops!" but his lips don't move. (01:16:10)
Audio problem: When Wanda asks Ken if he's heard from George Ken stutters "No, he had to go to the b-b-b", as it cuts we can see his mouth is closed. It's impossible to say "b" with your mouth closed. (00:02:50)
Audio problem: When the drunk driver steals Les's Caddy his nerdy friend says you can't take this car and Les says "He took our car, we're gonna take his" but his mouth doesn't move at all.
Audio problem: Lady Westholme pushes the half-open door against Poirot twice. The door makes the same sound it does when it gets slammed shut later (twice). As stocky as Peter Ustinov is, he's not made of wood, and while obviously a door hitting a person would make a thud (I admit having tested it), it wouldn't make the kind of sound heard here. (00:58:35)