Continuity mistake: Stewie tries to get his mind control device back from the kitchen. The cupboard door is open when he falls. In the very next shot, Lois turns the light on in the kitchen, and we see the door has closed without anyone touching it. It is open again after that.
Audio problem: When Peter goes down to the basement, the Pawtucket Patriot guy appears and Peter thinks he's coming on to him. He says, "Listen, I don't swing that way, pal. I got a date with my female wife, I just came down to get some beers." However, his lips very obviously do not sync up with those words.