1. A method comprising: transmitting, by an audio information channelization device, an audio stream in packet form, wherein the audio stream comprises a plurality of audio tracks that have been queued for playback by one or more playback devices of a synchrony group, wherein each audio track comprises a plurality of frames, and wherein each frame of the plurality of frames comprises audio information and an associated first time indicating when to play the audio information of the respective frame; receiving, by the audio information channelization device, a command, wherein the command identifies one of the plurality of audio tracks, and wherein the command indicates that the synchrony group should cancel playback of the identified audio track; based on the received command, ceasing transmission, by the audio information channelization device, of the identified audio track within the audio stream; after ceasing the transmission of the identified audio track, transmitting, by the audio information channelization device, a resynchronization instruction based on the received command, wherein the resynchronization instruction instructs the one or more playback devices of the synchrony group not to play back audio information associated with the identified audio track that has been previously transmitted within the audio stream by the audio information channelization device; and based on the received command, transmitting, by the audio information channelization device, a next track of the plurality of audio tracks that has been queued for playback by one or more playback devices of the synchrony group, wherein the next track includes a plurality of frames and a second time indicating when to play audio information associated with the next track of the plurality of audio tracks, and wherein the second time occurs after the first time.