2021-2022 Audi Speaker Rattles, Vibrations, or Audio Interference

Audi has released Technical Service Bulletin (TSB) 2018187/12 to address customer complaints regarding sound system issues in various 2021-2022 Audi models. This bulletin provides comprehensive guidance for technicians to diagnose and resolve speaker rattles, vibrations, or audio interference that can significantly disrupt the in-car listening experience. This TSB is an update, superseding an earlier bulletin, Group 91 number 20-39, issued on February 20, 2020. The revision incorporates updates for newer model years, specifically adding Model Year 2022 to the scope of affected vehicles and refining diagnostic procedures.

Symptoms

Owners may notice a range of undesirable noises coming from one or more speakers in their vehicle. These symptoms indicate potential Audi speaker interference and include:

• A cracking sound
• A grinding noise
• Rattling
• Humming
• Whining
• Other similar forms of audio interference

Technical Background and Diagnosis

The TSB explains that these sound system issues can stem from two primary sources. Firstly, physical vibrations can occur when parts of the speakers, such as their brackets, cables, or covers, or even components of the interior trim like door covers, the rear shelf, facings, or other covers, resonate at certain frequencies. This physical vibration can lead to the perceived rattling or grinding noises.

Secondly, the radio tuner or other control modules within the vehicle's sound system can be affected by electromagnetic interference. This type of interference is often caused by aftermarket electronic devices connected within the vehicle. This can manifest as humming, whining, or general audio interference.

To properly diagnose the source of the Audi speaker interference, technicians are instructed to follow a specific, systematic procedure. This methodical approach helps pinpoint whether the issue is mechanical vibration or electromagnetic interference.

1. Check for loose objects: The first step is to confirm that the interference is not simply caused by loose items stored within the vehicle's cabin, such as keys, CD covers, pens, or sunglasses. These items can vibrate against interior surfaces and mimic speaker noise.
2. Test for trim-related interference: Next, technicians are advised to push against the trim surrounding the affected speaker and also to push the speaker itself against its mounting points. If the interference does not disappear or change during these actions, it strongly suggests that the issue is not a simple loose trim piece or an improperly mounted speaker.
3. Isolate the speaker: A crucial diagnostic step involves removing the speaker from its mounting and listening to it while it is isolated from the vehicle's structure. This helps differentiate between speaker-internal issues and external vibrations.
   • If interference is no longer heard when isolated: This indicates the problem lies within the cabin fittings or the speaker's immediate environment. Technicians should then meticulously check for and fix any loose parts in the surrounding interior. This might involve tightening fasteners, applying sound-dampening material, or replacing any underlay material as necessary to prevent vibrations from transmitting to the speaker.
   • If interference is still heard when isolated: This points towards an electrical issue, most likely electromagnetic interference. Technicians should then investigate if any aftermarket electrical devices are connected anywhere in the vehicle, particularly those drawing power from a 12V power socket. Disconnecting power to such devices and rechecking the speaker for interference can confirm if they are the source. If the interference stops, the customer should be clearly informed that these specific aftermarket devices can generate electromagnetic fields that interfere with the vehicle's radio tuner and sound system.

Important Warnings

Audi states that this Technical Service Bulletin (TSB) is for informational purposes only and is not applicable to any Audi Warranty. Owners should be aware that repairs related to this TSB may not be covered under their vehicle's warranty.

NHTSA ID: 10201546