This is an audio slip up in the episode of What Goes Up. Bobby sprains his ankle and gets a pet parakeet from his parents. One day, it accidently gets loose from his room and Tiger, the dog, starts to chase it down the stairs with Bobby following right behind. Watch as the dog runs down the stairs. You can hear him barking, but look at his mouth. It isn't moving. Therefore, he couldn't be barking, yet you hear him.