BooseNot

Randomly out of nowhere, a buzzing noise was coming from my usb port area (where the phone charging bay is). Prior to that I had connected an external CarPlay device and was checking out some settings on the device extensively. Suddenly I started hearing a whizzing / buzzing sound - at first I didn't know where it was coming from but when I moved closer I realised it was the port area. I removed the device. turned off the engine. still nothing. I closed the car using the key and reopened and the sound was just there - static! really annoying but beyond that, somewhat concerning as it is not quiet/ When I close the port/cupholder cover, the sound gets buried but as soon as I open it again, the sound is there waiting to annoy further.
Should I be concerned? Does anyone recognise this issue and is there a solution? Going to Merc garage for this could be an unnecessary cost, especially if it is something so simple to resolve DIY. I await your kind assistance guys!

MJ50

what year???