See also:

Activating audio AUX mode
When you connect an external audio source, audio AUX is not selected automatically. Select Audio in the main function bar by sliding and turning the COMAND controller and press to confirm. ...

Center console, lower section - AMG vehicles
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Important safety notes
WARNING Grains of sand, particles of dirt and other abrasive materials can enter the brake system. This can lead to excessive wear and unpredictable braking efficiency. After the brakes have ...