In this case, it was being tired of classic rock from a lifetime of overexposure.
I would have said something like "I mean they call it classic for a reason, but I'm burned out on the same 100 songs all the time." That way you're acknowledging that their preference is valid, which is what they really want. Although I actually would have monologued for twenty minutes about Blue Oyster Cult and all their awesome songs that aren't Don't Fear the Reaper and Godzilla.