Audio problem: When Kevin plays the tape of his Uncle Frank singing in the shower, it starts with "We know a guy that can really do the cool jerk" twice. Yet, when he first tapes his Uncle, he doesn't start the recording until after that has been sung. The recording also sounds very clear. When he tapes him the door is closed, but the tape sounds the same throughout. Also, when his Uncle says he's gonna "slap him silly" Kevin shuts the door behind him and you can hear it shut. On the tape there is no sound of the door shutting.
Audio problem: When Kevin is singing on stage and Buzz is playing air drums by Kevin's ears, Kevin's singing is out of sync with the audio.
Answer: He's heading back to the hotel most likely to apologize for spending such a huge amount.