A computing device is configured to perform functions comprising: receiving via a network microphone device of a media playback system, a voice command detected by at least one microphone of the network microphone device, wherein the media playback system comprises a plurality of zones, and the network microphone device may be a member of a default playback zone. The computing device may be further configured to perform functions comprising: dynamically selecting an audio response zone from the plurality of zones to play an audio response to the voice input and foregoing selection of the default playback zone. The selected zone may comprise a playback device, and the dynamically selecting may comprise determining that the network microphone device is paired with the playback device. The computing device may cause the playback device of the selected zone to play the audio response.

An audio cancellation system includes a voice enabled computing system that is connected to an audio output device using a wired or wireless communication network. The voice enabled computing device can provide media content to a user and receive a voice command from the user. The connection between the voice enabled computing system and the audio output device introduces a time delay between the media content being generated at the voice enabled computing device and the media content being reproduced at the audio output device. The system operates to determine a calibration value adapted for the voice enabled computing system and the audio output device. The system uses the calibration value to filter the user's voice command from a recording of ambient sound including the media content, without requiring significant use of memory and computing resources.

The disclosure includes a method for using a doorbell system to detect a presence of a visitor. The doorbell system can comprise a doorbell having a speaker, a microphone, a camera, and a button. The method can include detecting, by the doorbell system, the presence of the visitor while the visitor is located outside a building to which the doorbell is attached. The building can include a door having a lock that is configured to fasten the door to inhibit unauthorized entry into the building. In response to detecting the presence of the visitor, the method can include the step of actuating, by the doorbell system, a first appliance associated with the building.

Embodiments described herein provide for detecting presence of an object in proximity to a playback device and responsively performing one or more operations. In an example implementation, a playback device detects, via a proximity detector of the playback device, presence of an object in proximity to the playback device. In response to detecting the presence of the object, the playback device performs one or more operations.

Example techniques involve identification of device groups. In an example implementation, a mobile device displays, via a control application, a synchrony group control including controls to select playback devices for a synchrony group. The mobile device receives input data representing a command to create a new synchrony group, the input data including input data representing selection of two or more playback devices for a new synchrony group. In response, the mobile device forms the synchrony group by receiving input data indicating a particular group identification for the new synchrony group, determining that the particular group identification is unique among other synchrony groups, and sending data representing instructions to the playback devices to form the new synchrony group with the particular group identification. In response to forming the new synchrony group, the mobile device updates an interface for the media playback system to indicate the new synchrony group.

Example techniques may involve guest access to a media playback system. A guest may use a guest control device, such as a smartphone or tablet, to control aspects of a host's media playback system. In addition, the guest may temporarily register their user account of a streaming audio service with the host's media playback system, which enables playback of audio content from that service by one or more playback devices of the media playback system. When the guest control device de-registers from the host's media playback system, retrieval of audio content from the streaming audio service is disabled.

Example techniques relate to audio generation in a media playback system. Based on one or more first functions and first characteristics of an area, the system may generate first audio that includes a first audio signal and a second audio signal. The system provides the first audio signal to at least one first audio driver and the second audio signal to at least one second audio driver, thereby causing a first playback device and a second playback device to play back the first audio synchronously. The system receives second characteristics of the area and based on one or more second functions and the second characteristics, generates second audio comprising a third audio signal and a fourth audio signal. The system provides the third audio signal to the at least one first audio driver and the fourth audio signal to the at least one second audio driver.

Examples described herein involve expanding playback of a media item from a first playback device to a second playback device. In one example, while a first playback device is playing a media item as part of a first zone, the first playback device identifies that a second playback device has moved to a location that is within a given physical proximity of the first playback. The first playback device determines that playback is to be expanded to the second playback device, and transmits a command to cause the second playback device to (i) join the first zone and (ii) begin to play the media item in synchrony with the first playback device.

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

An example implementation involves a computing device transmitting, via a local area network, a command that instructs a playback device to play a particular audio signal. The example implementation also involves the computing device receiving data indicating a detected audio signal corresponding to playback of the particular audio signal by the playback device, where the detected audio signal includes a portion of the particular audio signal. The implementation further involves the computing device obtaining data indicating a predetermined audio characteristic and determining an audio processing algorithm based on the detected audio signal and the predetermined audio characteristic. The example implementation involves causing the playback device to apply the determined audio processing algorithm when playing audio via at least one speaker.