[ctuna]

Only the L7 and EPS use the most bus for sound.
Unless something has changed very recently the HI FI amp uses
analog signals.
The Hi Fi amp does not connect to the most bus.
see following diagram.

http://www.e90post.com/forums/attach...1&d=1209780865

http://www.e90post.com/forums/attach...1&d=1209780605

BMW stereo types
http://www.e90post.com/forums/showthread.php?t=352586
http://www.e90post.com/forums/attach...2&d=1266451970
http://www.e90post.com/forums/attach...2&d=1260829447
http://www.e90post.com/forums/showthread.php?t=343673
http://www.e90post.com/forums/showthread.php?t=138949
http://www.e90post.com/forums/attach...2&d=1260829447


http://www.bawarec.ru/manuals/3er/e9...3er-e90-12.pdf
http://www.musicarnw.com/page-2/
http://www.e90post.com/forums/attach...4&d=1278871872

Xd600/6 is the most common replacement
It has the same number of channels and
fits in the stock location . It has the right preamp
inputs for the balanced output of the oem head unit.