15. The first NMD of claim 2 , wherein the first NMD comprises the first playback device.
15. The first NMD of claim 2 , wherein the first NMD comprises the first playback device. 16. The first NMD of claim 15 , wherein the first zone is configured into a zone group with a second zone, and wherein the functions further comprise playing back the audio content according to the playback command in synchrony with one or more playback devices of the second zone.