[AWD Addict]

2008 e92 with iDrive and 6fl. I have Logic7 sound.

A month ago, my audio (radio, auxiliary, everything) would start making occasional popping sounds, followed by audio cutting out. The audio would then come back on after a short time, and shut off again intermittently, and increasingly the longer I listened.

A couple weeks later, the problem had progressed and eventually audio wouldn't come on at all. The AUX input setting also began being greyed out completely. But all audio stopped, not just AUX. No other inputs were grayed out.

I've read about the L7 amp being a regular problem, and inspected. No water damage. I replaced the amp anyways, and the problem persisted. So it's not the amp itself.

It appears the audio only cuts out when the engine is running. When the key is on ACC only, the audio works. I can actually turn the car on, and it'll cut the audio, then turn it off, and a few seconds later, the audio picks back up.

Has anyone heard of this? Any thoughts? Could it be alternator or relay related (given the problem is only when the engine is on?).

[AWD Addict]

As my problem evolves, I'm finding it's not always working when on ACC either. Last night driving home, it actually only worked with the engine running, but would eventually cut out.

So strange

[ctuna]

Aux Graying out suggests it may be one of the modules in the Trunk Floor like Sat Radio , Mulf , TCU or Combox going out. There are so many thread here on how to troubleshoot a Most Bus problem. Get a Most jumper and rotate it through the module positions .

Also you should actually measure the battery voltage or you will chase your tail on a lot of problems caused by a low battery .
The battery is charged from under the Hood you don't have to take it out. Putting a full long slow charge on the battery is
always a good idea to do first.

[chiam]

I found this video about a simple way to check continuity through the modules in the trunk.

Here's the link:

[AWD Addict]

Incredible. My next idea was to buy a refurbished headunit, and I bought one from bavlogic, the creator of that video.

To his credit, he reached out and doubted my issue is the headunit, and discouraged me from buying it until the process in that youtube video was followed. Pretty cool move on his part.

I'm listening to that video, and I'm like "holy crap, is this the guy I talked to last week??"

Yep.

[AWD Addict]

After running through the MOST system, looping each individual component, it turned out to be a faulty Satellite Radio module in the trunk.

My mechanic looped the unit permanently, which put everything back in order. I don't use satellite radio anymore, so I'm not sure what I'm going to do. Part of me wants to put in another unit just for the sake of keeping all systems working, but a new unit is over $900, so I might just punt for now.

[ctuna]

You can pick those on Ytube cheap.