Sleep modes for plugged-in players

A playback device comprising:

• a communications interface including a wireless radio;
• one or more speakers;
• one or more amplifiers configured to drive the one or more speakers;
• at least one processor;
• and
• at least one non-transitory computer-readable medium comprising program instructions that are executable by the at least one processor to control the playback device to:
• using the one or more speakers and the one or more amplifiers, play back at least one channel of audio content synchronously with playback of at least one other channel of the audio content by at least one other playback device in a bonded group;
• determine, while the playback device is in the bonded group with the at least one other playback device, that the playback device has not received, for a predetermined time interval, control information that instructs the playback device to play back the audio content;
• based on the determination, cause, via communication of at least one message to the at least one other playback device in the bonded group using the wireless radio, the at least one other playback device to enter a suspended state in which the at least other playback device suspends an operating system and one or more programs, the one or more programs including a control program configured to instruct the at least one other playback device to play back the audio content;
• monitor for a wake-up indicator while the at least one other playback device in the bonded group is in the suspended state;
• and
• based on detecting the wake-up indicator, cause, via communication of at least one message to the at least one other playback device using the wireless radio, the at least one other playback device to resume execution of the operating system and the one or more programs.

A method of operating a plurality of playback devices configured as a bonded group, the method comprising:

• determining that, for a predetermined time period, the bonded group of playback devices has not received control information directing the bonded group of playback devices to play back audio content;
• based on the determining, selecting one or more playback devices in the bonded group to identify a subset of playback devices to enter a suspended state;
• and
• sending sleep instructions to the subset of playback devices to cause each playback device in the subset of playback devices to suspend an operating system and one or more programs, the one or more programs including a control program configured to instruct a respective playback device to play back the audio content in synchrony with other playback devices in the bonded group.

A playback device comprising:

• at least one processor;
• one or more speakers;
• one or more amplifiers configured to drive the one or more speakers;
• a communications interface including a wireless radio;
• and
• at least one non-transitory computer-readable medium storing program instructions that are executable by the at least one processor to control the playback device to operate in a bonded group comprising the playback device and a plurality of satellite playback devices, to operate in the bonded group comprising to
• determine that the playback device has not received, for a predetermined time interval, control information that instructs the playback device to playback audio content;
• identify, based on one or more capabilities of the plurality of satellite playback devices, a first subset of the plurality of satellite playback devices and a second subset of the plurality of satellite playback devices, and
• send, via the wireless radio, sleep instructions to the first subset of satellite playback devices to control each satellite playback device in the first subset of satellite playback device to suspend an operating system and one or more programs, the one or more programs including a control program configured to instruct the satellite playback device to playback the audio content.

A playback device comprising:

• one or more speakers;
• one or more amplifiers configured to drive the one or more speakers;
• a communications interface including a wireless radio;
• circuitry comprising a plurality of processors including one or more first processors and one or more second processors;
• and
• at least one non-transitory computer-readable medium comprising program instructions that are executable by the plurality of processors to control the playback device to operate in a bonded group comprising the playback device and at least one other playback device, to operate in the bonded group comprising to
• after a first predetermined time interval during which the playback device has not rendered audio content, receive, via the wireless radio, sleep instructions from the at least one other playback device in the bonded group,
• based on detecting the sleep instructions, suspend an operating system and one or more programs, the one or more programs including a control program configured to instruct the playback device to render the audio content,
• detect, via the wireless radio and the one or more second processors, a wake indicator from the at least one other playback device in the bonded group, and.
• cause, using the one or more second processors, the one or more first processors to resume execution of the operating system and the one or more programs.