oh dear old chap. if you try to endear yourself to her by trying to bluff about a subject you know nothing about, then you're destined to crash and burn spectacularly. by far the better approach is to ask her about the music she likes, why she likes it so much and generally show interest in her and her interests. also talk to her about the music you like, why you like it, etc.
you may find some common ground, in which case great, or the only common ground you may find is that you both like (different) music for the same reasons.
or you may find no common ground on music at all, which is a setback, but not a killer. there are many other areas of life to share.