In the episode "Me and Rico Down by the School Yard," If you look really closely when Rico is on Miley's lap, after she says, "You're on my lap, aren't ya?" The camera shot changes and her facial expression changed from a forged smile and looking at Rico, to a frown and looking away from him. Normally this wouldn't be a slip up, but there is no significant time difference time difference between the two shots (if any), so she changes it faster than possible.