Pretending you know the band just to fit in means you’ll have to fake the lyrics too.

One small claim made to fit in commits you to keeping it up, and the maintenance is the part that wears you out. It also quietly ruins the thing you were after, since belonging built on a version of you that does not exist never quite feels like belonging. You end up in the room and still outside it.

Try saying you have not heard of it, plainly, at the next chance. Ask them where to start. People generally enjoy being the one who introduced you to something, and that conversation beats the one you were about to fake.