Person failing to sing along the radio

Hi,

I’m thinking of a movie scene in which a person is or rather wants to be enthusiastic about something that just happened. He or she is in the car, tuning the radio and totally failing to sing along because of the lack of knowing the lyrics, in a way realizing in this moment, what just happened was nothing to be proud of – until finding a station playing some dull song he/she still can easily sing to.

Any idea which movie this is? Sorry – if I had any clearer image of the actor/actress I’d probably already knew the answer myself.

Cheers,
Mac