Well THAT was odd... (E82 factory stereo content)

[02Pilot]

Out running a few errands this morning. In and out of the car a bunch, so I left the stereo on (automatically shuts off when I shut down, comes back on when I restart the car, as usual). I come back the car after several such cycles and hear a loud buzzing coming from the rear of the cabin. Check in the trunk and underneath to determine it's definitely loudest inside the cabin. Stereo on, stereo off, doesn't change it. Ignition cycled doesn't change it. Nothing seems to affect it. Drive home annoyed with the buzzing in my ears....

Get home, decide to start troubleshooting. Before pulling the fuse I figure I will try to isolate the source. I adjust the balance full left and as I hit +10, the stereo display cuts off and the noise goes away. Cycle the stereo - now everything is fine. No buzzing, all speakers normal. Hmmmm....

Any thoughts on what just happened here? 2009 128i, standard stereo with factory satellite tuner (which was in use when the problem occurred). I hate intermittent electrical problems with a passion, so any suggestions on how to squash this would be most appreciated.

[Pelican Parts]

Hello - my guess that it may be fuse related; just because you said that that after hitting +10, the stereo's display cut out. I'm assuming no codes were thrown? I have an 08' 135i and haven't come across this issue myself. Other members will likely chime in with their thoughts. Btw, big fan of that motor - one of the last NA incline 6 they made.

[02Pilot]

I didn't check for codes - I'll try to remember to throw the scanner on it tomorrow. My next step was to pull the fuse, but it never got that far. I should take a look at that tomorrow too. On another forum one user said he had exactly the same experience once, but it never recurred.

I'm quite happy with the N51 thus far. I go back a long way with BMW straight sixes, from the M30 in my 533i to the M54 in my 525i, so it's nice to keep the run going.