Morkus from Orkus
Open your mouth wide and breathe out. Then purse your lips to whistle. It's not the air, it the interface between the air and the music that provides the music. Whether that interface is your voice box, your lips or an instrument of some kinds, it's not your breath alone that does it.Magic dead areas are non-existant. They break too much crap, and cause too many headaches with "Well, My paladin's aura doesn't say it is a magical effect suppressed by anti-magic."
And, if you are talking a bit of nonsense in the terms of music. The sounds is the movement of air. Your mouth is moving the air. There is no middle step where you mouth interfaces with something and that something moves the air. The physical thing that is the sound is created directly by your actions, not by an intermediary force.