Audio fingerprinting

A rights holder supplies a reference recording, the system reduces it to a compact acoustic signature, and every upload gets compared against that library. Matching survives volume changes, pitch shifts, background noise and re-recording through a speaker, which is why muting the music a little or playing it from across the room achieves nothing. YouTube's Content ID is the best known implementation. Being matched is a long way from being punished. The claim tells you what was found, and your options are to dispute it, trim it, mute the section or swap the track in Studio's editor.