See also:

Multi-channel playback,surround
Choose between stereo and multi-channel playback, surround. Setting multi-channel playback, surround 1. "CD/Multimedia", "Radio" or "Settings" 2. "Tone" 3 ...

Office
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Priority options
The driver has priority The source selected via iDrive in the front is output on the vehicle loudspeakers and can be selected but not operated from the rear. Other audio or video sources ...