The rear speaker located in the trunk is really noisy, like gunfire
My car has 32000 miles.
My car has an automatic transmission.
Perhaps your factory-installed speakers have failed? If your Mercedes is still under warranty, you might pursue this problem with the dealer under warranty repair. The age of your E350, and mileage would certainly indicate this as appropriate. If dealer repair does not resolve the problem, I would check with your favorite local car audio vendor, or Crutchfield (long-time Internet/mail-order car audio supplier). Car audio forums like http://www.diymobileaudio.com/ can also be very helpful.
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