Audio problem: On the video, when Molly is standing at the laundromat calling Neal on the payphone, she is saying "pick up the check, spank the brat, I am woman, how 'bout you?" you can see that her lips do not match the line "how 'bout you?".
Audio problem: Just after Molly gets fired and she sees Neal while crossing the street, he says something like, "...been able to write a decent song since I last saw you..." His lips don't match what he's saying.
Audio problem: In the scene at the end where Ray and all the other ballerinas are dancing with the guitars, at the very end of the song when everyone starts clapping, you can see that the guy Molly was dating in the beginning, who is supposed to be singing and playing guitar in that moment, he's actually clapping his hands, but the audio playing sounds like he is still playing the guitar and singing.
Answer: A part of a song which grabs the listeners attention.