Continuity mistake: When the seven dwarves run scared down the stairs and out of the door, Dopey pulls the handle of the door from the inside until it breaks out and falls away. The next scene when the dwarf opens the door, the handle is there again. (00:33:00)
Continuity mistake: After the hands draw the concert hall, the lion conductor walks out on stage to address the crowd. He stops in the center of the stage and turns, facing straight forward towards the camera. But then it cuts to a close up and suddenly his body is facing to the left. You can also tell by his shadow that he is suddenly much closer to the curtain behind him. (00:01:35)
Audio problem: When the man is in the Desert Inn in the film that is being shown at the theatre, he asks for the waiter, but when the film is being shown in reverse towards the end of the cartoon, no words are coming out when this happens.
Continuity mistake: When Porky arrives home, you can see a window looking outside to the right of the front door, but when Porky shoots the man upstairs a second time, the front door now leads to a hallway with a staircase.
Continuity mistake: When Goofy searches through the dresser drawers one of the ghosts causes trouble, then Goofy breaks through the top of the dresser and winds up trapped inside, but when all four ghosts appear the dresser top is perfectly fine and that damage has vanished. Also, two of the drawers (one large and one small) fall out of the dresser, but as the four ghosts are pushing the dresser those two drawers have reappeared in their proper places.
Continuity mistake: When lawyer Goodwill is in the secret laboratory, he picks up a bottle that has "Jekyll and Hyde Juice" written on the label, but when we see him with the bottle in the next shot, the words have disappeared.