High-frequency interference noise may be heard from the speakers while driving

Bulletin number

LI82.85-P-069851 (LI82.85-P-069851)

Component

Electrical system

Summary

High-frequency interference noise may be heard from the speakers while driving. This complaint only occurs when "voice amplification" is active. Coupling noise of microphone signal in voice amplification. Intermediate remedy: The interference noise can be remedied by deactivating voice amplification: "Home" -> "Settings" -> "System" -> "Audio" and de-select "Voice amplification to rear" to switch off the function (see attachment). Note: To activate or deactivate the function, the ignition must be switched on, seat belts (at rear and front) must be fitted and the doors, windows and roof must be closed. Permanent solution: Perform software update of MBUX multimedia system (A26/17) to E419.5 (available from 06/19) or greater. Deactivate the ‘voice amplification’ feature. Inform customer of function and effects of additional sounds caused by driving over bumps or uneven road surfaces.

Owners of these vehicles have filed 127 complaints in the electrical category.