AudioSettings.speakerMode
static var speakerMode: AudioSpeakerMode;
Description

Sets or gets the current speaker mode. Default is 2 channel stereo.

Be aware that the audio system is restarted when a new speaker mode is set. This means that playback on all AudioSources is stopped; any sounds that should be continuous (such as music) will need to be started again after the speaker mode is changed. If a speaker mode is set beyond the drivers capability, the audio behaviour is undefined. Use AudioSettings.driverCaps to get the capabilities of the current driver.
	// To set the speaker mode to that of the system settings.

AudioSettings.speakerMode = AudioSettings.driverCaps;