For some elusive reason, my New 3DS speakers stopped playing audio after a few weeks. You need earphones to hear it. I can verify that the system audio is tied to the Mic function. In Fire Emblem Fates, when I have to blow steam off my spouse, I have to time it out. In Animal Crossing, when I have to blow birthday candles, I have to time it out. The only item completely disabled is the megaphone.