Audio problem: Aunt Millicent checks on the sleeping children and in the shot outside the bedroom we hear the sound of her closing the door. However when she is startled by her true shadow we see the bedroom door has been left ajar. (00:14:30)
Audio problem: Peter tells Wendy, John and Michael, "There are mermaids! Indians! Pirates!" We hear the children repeat, "Pirates!" but their mouths do not actually say it. (00:22:45)
Audio problem: When trapped underwater in the net at the Black Castle, Peter pulls out his knife from his small leather sheath underwater and we hear a metallic rasping sound which it should not make since it isn't scraping metal. (00:49:55)
Audio problem: Wendy is tied to the mast on the Jolly Roger when Hook forces her to tell a story. In the wide shot, the pirates start to find seats and Hook has his hand at Wendy's throat as we hear her begin, "There was a boy named Peter Pan," yet her mouth does not move. She continues to say off camera, "who decided not to grow up," and in the next shot Hook gets angry and tells her to skip the prologue. (01:18:00)
Answer: In day for night filters (which is what was used to film that scene to make it look like nighttime) Asian people can look quite eerie. And since the mermaids are supposed to be dark creatures, if they actually look eerie that makes the scene fit better.