A method performed by a first playback device in a network media system, the method comprising: while an amplifier in the first playback device is in an inactive state, detecting, by a proximity sensor on the first playback device, a first movement within a first range of distances in relation to the first playback device, wherein, in the inactive state, the amplifier is in a lower-power mode or a powered off mode and media content cannot be rendered by the first playback device until the amplifier is activated, and wherein, in the inactive state, a communication interface of the first playback device remains active while the amplifier is inactive; and responsive to the detected first movement: causing, by the first playback device, the amplifier to enter an active state, wherein, in the active state, components necessary for rendering media content are active so that rendering of media content may occur immediately in response to a user input to cause the playback device to render media content; sending, from the first playback device to a second playback device (1002, 1004, 1006), an activation message that causes an amplifier of the second playback device (1002, 1004, 1006) to enter the active state; detecting by the proximity sensor on the first playback device, a second movement in relation to the first playback device within a second range of distances from the playback device, wherein the second range of distances is nearer to the first playback device than the first range of distances; and responsive to the detected second movement, retrieving media content from a networked audio source; and storing at least a portion of retrieved media content on a data storage medium of the first playback device. while an amplifier in the first playback device is in an inactive state, detecting, by a proximity sensor on the first playback device, a first movement within a first range of distances in relation to the first playback device, wherein, in the inactive state, the amplifier is in a lower-power mode or a powered off mode and media content cannot be rendered by the first playback device until the amplifier is activated, and wherein, in the inactive state, a communication interface of the first playback device remains active while the amplifier is inactive; and responsive to the detected first movement: causing, by the first playback device, the amplifier to enter an active state, wherein, in the active state, components necessary for rendering media content are active so that rendering of media content may occur immediately in response to a user input to cause the playback device to render media content; sending, from the first playback device to a second playback device (1002, 1004, 1006), an activation message that causes an amplifier of the second playback device (1002, 1004, 1006) to enter the active state; detecting by the proximity sensor on the first playback device, a second movement in relation to the first playback device within a second range of distances from the playback device, wherein the second range of distances is nearer to the first playback device than the first range of distances; and responsive to the detected second movement, retrieving media content from a networked audio source; and storing at least a portion of retrieved media content on a data storage medium of the first playback device. causing, by the first playback device, the amplifier to enter an active state, wherein, in the active state, components necessary for rendering media content are active so that rendering of media content may occur immediately in response to a user input to cause the playback device to render media content; sending, from the first playback device to a second playback device (1002, 1004, 1006), an activation message that causes an amplifier of the second playback device (1002, 1004, 1006) to enter the active state; detecting by the proximity sensor on the first playback device, a second movement in relation to the first playback device within a second range of distances from the playback device, wherein the second range of distances is nearer to the first playback device than the first range of distances; and responsive to the detected second movement, retrieving media content from a networked audio source; and storing at least a portion of retrieved media content on a data storage medium of the first playback device.