KnappAttack

So I have a vibration in the rear shelf. Had it to the dealer and he tells me its a blown sub woofer on my Bang&Olufsen audio system. Of course its $1600 to replace it and Audi will not warranty it with CPO. He said the speaker was loose and they tightened it up but rattle was still there when turned up, so figured I'd try it before spending that kind of money on just a sub woofer. Well it has gotten worse over time. It used to sound supreme. Now I just cant take it anymore. I can't turn the music up at all with it rattling in the back shelf. To me it sounds as though as something has come apart in the shelf itself. These high end speakers should take what ever you can throw at them, even the dealer told me that. I've tried to take things apart myself from inside the trunk to no avail. Does someone know how this shelf comes apart so I can see for myself what is happening back there?

Anyone else had this happen on their A8 with B&O? It seems common with some other models of Audi's with owners complaining of speaker or shelf rattles, but find no such issues on the 8 when I do a search. I know its not the speaker grills either. If I push on the shelf from below inside the trunk, it appears to rattle less which leads me to believe its in the shelf and not the speaker like dealer is saying.

If it is the speaker, I wonder if there's other options out there besides the expense of the factory $1600 replacement speaker. I have to fix it as its driving me nuts. I can just see the dealer replacing the speaker and having the rattle still there, or learning its just the shelf rattle or something coming apart and still getting a possible $1600 bill.

Jack88

A blown speaker can cause a vibration which will in turn rattle the shelf, so a reduction in vibration holding the shelf may not be an indicator that the speaker is not blown. There is no way to remove the shelf without damaging the speaker trim. In addition to the speaker trim requiring to be removed, there is the seat backrest, rear armrest upper trim, c-pillar trim, d-pillar trim, and seat belt guides. The shelf needs to be pried up from there, with care taken to detach it from the window shade.

MP4.2+6.0

I would get a manual on technique to pull rear shelf. I did it perfectly cleanly on D3 for window tinting. Probably involves pulling rear seat back, likely a lot of rear trim all around glass (removal may be top down like D3), and going in from trunk to remove some screws and electrical connectors. It is pretty involved on D3 and you would not guess all the tricks or steps w/out a manual to explain.

For part, how about frankly EBay? Yeah used, but not $1600. Look at ebay.de (Germany) too for more availability. Gotta deal with the Deutsch, but if you search by part # you can find something often and then wash page through a translator if you can't make out the basics like year, miles, condition, etc. The smaller and lighter the part, the more likely someone will ship if of some value. Some advertise shipping, some you have to write and some others never respond. Has worked for me a fair % of time if not listed here, but it is there. Use the whole EU search option to get broader reach too. You can also try from the UK site (ebay.co.uk), but often I find listings with no English just don't get picked up that way even if you say you want to search whole EU.

Jack88

The speaker trim has to be removed to access screws to separate the speaker from the shelf for removal. If you can remove that trim without breaking the clips, hats off to you.

BigBoy11

Going to sound unlikely but you might also want to check any items you have in the trunk and/or back seat especially in the floorboards. When my trunk is empty or has minimal items in it and little or no items in the backseat or floorboards, there is absolutely no rattle no matter how high I turn the B&O volume. But if I have the car packed for a trip and especially if there are items in the backseat area, the rattle is so pronounced I can't stand to listen at any volume. Sounds bizarre but happens every time. Only thing I can figure is some type of harmonic distortion going on and the dealer has tried everything they could think of to replicate the issue. Worth a shot and certainly less than $1600!!!

KnappAttack

I thought about taking the car to a local stereo shop, but man I don't want any damage to the trim pieces ect. I have no problem performing any mechanical repairs including tearing down engine, transmission, ect, but the inside trim stuff I have no experience with and this sounds a bit complicated if you don't know the techniques.

If I blew the factory B&O speaker whats to prevent it from happening again? Maybe a good aftermarket speaker would work better?

Local car audio shop perhaps? Scary thought if they don't know the techniques on getting an A8 apart either.

the_duke

I wouldn't take my A8 to a stereo shop. You would probably have better luck with a independent Audi specific mechanic. Most stereo shops have never seen an A8.

andrewmr

Mike.... quit listening to rap music

in all seriousness, you say the Audi tech tightened up the speaker. Perhaps it's worth talking with them to see how far they took it apart to get to the screws to tighten them.

And then if they knew what all is involved to get the speaker out.

I'd call a high end stereo shop to ask them about a speaker replacement.

CurlyStooge

Here's the cheapest first option: go to https://erwin.audiusa.com. Register for free, then pay $35 for a day pass to access all the Audi manuals mechanics use. Download all of them to your pc. Then find the manual with instructions to remove B&O sub from rear shelf. Mine is in the Communication manual. I did this for my A6 to remove my B&O sub from rear deck. Super easy. Take the sub out and bring it to a good car audio store to do bench tests to confirm it's damaged. I'd be shocked if you blew the sub because max volume is set well below amp's and sub's capacity. If it is blown, I'll sell you mine for half that price. I'm replacing it with a JL W6 10". BTW, mine was rattling too, so I placed some dampener (like Dynamat) on the rear metal shelf and it all went away. When you get the rear shelf trim out to expose the metal shelf and sub, play some music with deep bass and sit in the rear seat to hear where the rattling is coming from. Press down on the metal shelf with your hand to dampen any vibrations to isolate the sub. You may get lucky and not have a bad sub but poor vibration dampening from factory. Let us know how you go. Best.

MP4.2+6.0

I can't add much on the technical side or experience resolving this issue. But, I was a little surprised by what I saw below the shelf on a 2015 S8. I was under there because I was looking at both the ski sack and rear window tint degree of difficulty---per other recent posts. I was somewhat surprised to see some sort of rough openings in the area under the shelf accessible from trunk, and somewhat visible parts, wiring and assemblies up in the exposed areaa--as in, it wasn't all covered up and maybe there is some stuff in there that could vibrate. Perhaps it is reachable or findable from underneath with no disassembly. You could maybe Dynomat at least some of the sheet metal a lot easier from the trunk side, probably assuming the punched openings in the metal should not just be covered over. You would pull the trunk lining away temporarily to get at it better. I'm guessing some of the uncovered patches may be intended to deal with the speaker induced air movement, but I have seen (on D3) cleaner implementations relating to moving air from cabin to back as part of flow through ventilation design.

Yes on the power side too; I noticed volume control peaks at 34 and B&O can drive it there cleanly with good source material and not exaggerated (pumped up) tonal settings. But then I also saw in Hidden menu what I can guess (since it said 34) is the pre set limit field that drives the max volume control. They also had it for phone and Nav volume. Under circumstances probably not what you want to do to exacerbate existing issue, but I think I found the override to this particular limiter.