Configuration of playback device audio settings

A system comprising a first playback device and a second playback device, wherein the first playback devices comprises:

• a network interface;
• at least one processor;
• and
• data storage including instructions that are executable by the at least one processor such that the first playback device is configured to:
• receive, via the network interface from the second playback device over an unsecure network, a message indicating that the second playback device is available to join a playback network, wherein the first playback device is connected to the playback network;
• based on pre-existing configuration data, determine an audio setting corresponding to a bonded playback configuration for the second playback device, wherein the determined audio setting is stored in the pre-existing configuration data prior to the first playback device receiving the message indicating that the second playback device is available to join the playback network;
• transmit, via the network interface, one or more messages instructing the second playback device to form the bonded playback configuration corresponding to the determined audio setting, wherein, while the bonded playback configuration is formed, the first playback device is configured to play back one or more first audio channels of multi-channel audio content and the second playback device is configured to play back one or more second audio channels of the multi-channel audio content;
• and
• after formation of the bonded playback configuration, play back a first portion of particular audio content in synchrony with playback of a second portion of the particular audio content by the second playback device.

A method to be performed by a first playback device, the method comprising:

• receiving, via a network interface from a second playback device over an unsecure network, a message indicating that the second playback device is available to join a playback network, wherein the first playback device is connected to the playback network;
• based on pre-existing configuration data, determining an audio setting corresponding to a bonded playback configuration for the second playback device, wherein the determined audio setting is stored in the pre-existing configuration data prior to the first playback device receiving the message indicating that the second playback device is available to join the playback network;
• transmitting, via the network interface, one or more messages instructing the second playback device to form the bonded playback configuration corresponding to the determined audio setting, wherein, while the bonded playback configuration is formed, the first playback device is configured to play back one or more first audio channels of multi-channel audio content and the second playback device is configured to play back one or more second audio channels of the multi-channel audio content;
• and
• after formation of the bonded playback configuration, playing back a first portion of particular audio content in synchrony with playback of a second portion of the particular audio content by the second playback device.