US Patent 10433057 Wireless audio synchronization

An audio distribution system includes an audio source; and a plurality of audio playback devices in communication with each other and with the audio source. A group of the audio playback devices are arranged to render audio content provided by the audio source in synchrony. One of the audio playback devices within the group is configured as an audio master which distributes audio content from the audio source to the other audio playback devices within the group, and one of the plurality of audio playback devices, other than the audio master, is configured as a clock master, which distributes clock information that the group of audio playback devices synchronizes to.