2014 Mercedes-Benz E350 electrical system problems

There have been three events, all the same. Each time a speaker in a door, while driving, has began to squeal, sputter and the smoke. The first occurred while sitting inside a car wash, with the windows up, obviously. I was able to open the window, drenching myself, but venting the acrid electrical smoke. The second was while driving home from a medical clinic.

I was traveling on highway 26 at approximately 60 MPH getting ready to merge onto highway 526, when the entire digital warning panel lit up and then went dead, with the engine inoperable light coming on and asking me to refer to the owners manual. All power was cut from the gas pedal and I was lucky enough to be able to coast to a very small strip of median without being hit by any other vehicles.