When Katie and Charlie are on the train and toasting the Chinese food boxes, they are open. Then the camera-shot turns to the outside of the train and the boxes are closed.
Also at the first shot Katie hold the food box with her left hand, at the outside of the train shot she holds it in her right hand.
Also at the first shot Katie hold the food box with her left hand, at the outside of the train shot she holds it in her right hand.
When Katie is recording the song, the Audio-Technica headphones are the wrong way on her head. The L and R letter are on the shiny hinge, and L is visible on her right ear.