For all we know the dealers might have a technical bulletin with a known cause/fix.
There's two:
Technical product information Transaction No.: 2051556/3
Sound, A4/A5: rattling noises from door speakers or subwoofer Release date: 17-Aug-2018
Customer statement / workshop findings
Noises from the door speakers.
Technical background
Software issue
Production change
Saloon: Week 23/18
Avant: Week 23/18
Sportback : Week 22/18
Coupé : Week 22/18
Cabriolet: Week 19/18
Saloon China: Week 24/18
Measure
Complete TPI 2017958 and assess whether the complaint is caused by the speaker itself or by body vibrations. If the
speaker can be identified as the source of the noise after removing it an and holding it in your hand, perform the SVM
code 47A006 in the tester menu under Update.
Check whether the complaint is fixed. If not, replace the speaker.
Warranty accounting instructions
For accounting according to the warranty guidelines with Audi AG/the importer observe the following accounting
instructions:
Service number/damage code: 9140 / 0040
When improving the sound insulation of the speakers, use service number of the noise-causing component.
Groundlessly accounted work/replaced parts will be redebited.
Technical product information Transaction No.: 2051047/2
A4, A5: noises from dash panel speaker cover Release date: 12-Jun-2018
Customer statement / workshop findings
Noises from the middle speaker cover of the dash panel in music or phone operation.
Technical background
Vibration noises because of movement between cover and carrier.
Production change
Speaker cover with nonwoven fabric over whole surface.
Measure
Remove the speaker cover with a small plastic wedge.
Note:
In winter the cover should not be removed when it is cold, as the clips could break and fall into the dash panel.
This could cause noises when driving.
Replace the cover with a new with integrated nonwoven fabric.
The part numbers are 8W1819899 or 8W2819899.