I have an 06 M35x and my car's audio system is totally unresponsive!! I searched on here and it seems that there was no solution found. Anyways, so here's what I've done up to now:
-Ran the self diagnostics mode and found that the "audio unit" is non-existent.
-Looked at the AV section of the FSM to troubleshoot the issue.
-Ruled out the amp because I can still get navigation alert sounds.
-Tried changing out the head unit, multifunction switch and the NAVI control unit with good working parts, problem still persists.
So, now I'm my head against the wall trying to figure this out!! Is there anyone currently here who encountered this issue either currently or in the past that can point me in the right direction?? I would greatly appreciate it!!!