Music protector, of a sort

CDCASE

Think of where you might store a disc to keep it safe from scratches—this four-letter container often sits on a shelf.

A "music protector" hints at something that holds or safeguards music, like a CD case. The "of a sort" part signals it’s not literal—CD cases don’t actively protect music but keep discs safe. The answer plays on the idea of storage as a form of protection, with "CD" standing for the music format and "CASE" as the container. It’s a straightforward definition with a slight twist in framing.