[ctuna]

IN the Most Bus system that BMW setup this is and optical Bus Ring in which add on modules are connected to add functions like Sat Radio or Bluetooth phone Sos in the Logic 7 system the amp is also part of this optical bus ring.
The Head Unit can be considered the Server or controller for the Most Bus.
All the Inputs and control for the Amp and these other modules are dependent on every module in the Ring working.
So the amp gets control signals and the audio input from the head unit via
the Most Bus. The code BMW proprietary as far as I know but some of the other German Car makers used this system .
Some of the problems are if one module in the system fails all the others stop working .
Read the Links on Logic 7.

Hi Fi amps made after 2011 are Silver . and half the size of the Logic 7 amp.

This stuff is covered in the links if you read them .

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