Continuity mistake: When Max runs in the bathroom to complain about Duke, the bathroom door opens into the bathroom against the tub, but when she pushes Max out of the bathroom the door suddenly is on the other side of the door frame opening outwards into the living room. (00:12:20)
Continuity mistake: When Snowball goes in the ocean to save Max and Duke it's morning, but when they come back up it's night. (01:13:17 - 01:14:25)
Suggested correction: It is supposed to be the afternoon.
Other mistake: Duke is running through the city while dragging Max by his leash. A close-up shows Max being pulled between the bars of a metal fence, but the gap is much too small for Duke to have passed through.
Audio problem: The Rabbit leads the two main dogs past the snakes with the password. The first few words he says, his mouth isn't moving.
