IknowHuhA6

About a month ago, I got in my car to go to lunch and realized there was no volume on the radio. That was odd considering radio is always on.
Went to raise volume but Nuffin!!
I cycled though all MMI buttons and muted/unmuted, Off/On but the radio just would not work. I selected SD card media and still no sound. Tried CD's and the display showed it was playing but no sound. My speakers seemed to be dead. When I got back into car and restarted after lunch everything was fine again.

This weekend once again... the speakers failed. No radio/SD/Navigation directions sound. When I raised volume **** this time I got a "not available" display in MMI. DOH!
I pulled off Hwy, restarted car, reset MMI multiple times and NUFFIN!!
Got to my destination and restarted car couple hours after and all worked again. Ugh!

Searched but didn't find much, then came across this thread for different model but seems to match my situation, which leads me to believe maybe my Bose Amp is failing. Anybody else come across similar situation?

https://www.audiworld.com/forums/a6-...sound-2896009/

jjsC6

I've had it happen once, but that was several months ago and it has not done it since. Have you tried closing then reopening your windows

DanfZX14

IknowHuhA6 - My first guess would be the Bose amp if you checked all the connections you have access to and verified that the pertinent fuses are properly seated as in the link you have in your post. Something else to consider is did this problem show up right after any of the recent mods you may have done??? If so you may want to try undoing it. If not I'd start looking at the amp...

ursur

I've had the volume not available problem once or twice, although not recently now that I think about it. When it happened to me, it was shortly after starting the car and either after switching sources or modes (nav to radio or media or something like that), so I assumed it was still booting up as it would work a minute or two later.

I thought it was weird that volume control would be something that I'd have to wait to finish loading to be available, but now that I think about it, I don't think I've had the problem since the dealership upgraded my MMI software to 814 (or whatever the latest version is currently, don't remember the number exactly) when I had problems with my Bluetooth connection.

Never had the no sound at all problem though, so maybe it's not related.

1st Time Audi

Same as ursur with me. Sometimes it's not available up to a few minutes after starting the car up, but then comes up.

IknowHuhA6

Yes tried that too and was even played music on my phone trying to coach the system to work... c'mon you can do it I kept saying.

Only majormod I had done was the active lane assist, and no wires or controllers were touched that would affect the MMI system. That mod was simply steering switch, steering wheel and coding.

Can you please post what MMI version you have. Just curious. Either way if it's MMI, since I"m out of warrant its well into $1K for upgrade, same price as new Amp. I'll need to keep doing some research so I'm not throwing money at trying to solve a problem. It's only happened twice so far.

Thanks guys.

DanfZX14

My MMI Version is HN+R_US_AU_P0733.

Just for the heck of it I looked on eBay and used Bose amps for that vehicle run $300-400.

IknowHuhA6

Yeah but I'd be going from my worn out unit to another used unit. Don't think I like those odds. After my years of experience retrofitting things.. the one HARD lesson I've learned is that whenever possible... electronic components never buy used. That's just my personal philosophy.
For the shorter lifespan of these I might as well buy a new unit and it will last longer than the shorter lifespan of a used unit, and i'm stuck replacing it over and over again more frequently because I skimped on a new unit.
Mechanical components are a different story however.

I guess maybe if I come across a new MY lower mileage amp, that may be worth a risk.

Oh.. and thank you for the MMI version. I'll have to compare.

DanfZX14

I also ran across these guys in my travels in case you find out it is actually the amp and you want to consider having it repaired.
Acura, Cadillac, Chevrolet, Corvette, Nissan, Infiniti, Mazda - BOSE, Stereo, Amp / Speaker Repair

thehedge

I've had a similar problem with the volume in my 2012 A6 Prestige but mainly with just the AM radio. I can switch sources and the volume will be the normal levels but if I switch back to AM, it will be so low that I have to turn the volume up almost to full before being able to hear it. For me, power cycling the MMI does not fix the problem BUT turning the car off and then back on again does.

It has only happened a few times and there have been no codes left when reporting the issue to my mechanic and (naturally) by then, the problem has fixed it self so is no longer present for diagnosing.