Eh number 3 can happen to any car. My 2002 4.4i with stock audio sometimes makes things rattle, too without turning it up.

The best course of action is to book some time with the dealer's shop foreman and attempt to re-produce each of the problems. Take as much time as you need to re-produce the problems since the foreman gets paid to ride around with you, too.

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2008 ML320 CDI | Iridium Silver | Black ARTICO Leather | Premium Package (H/K Logic7, Parktronic, Rear Heated Seats, Rear Power Hatch, DVD Nav, 10-way Front Seats w/ Memory) | Backup Camera | Aluminum Running Boards | 4500K MTEC Low-beam HID | 30% Metallic Tint | Boomerang2 Recovery System | Weathertech Front Floorliners | Bridgestone Blizzak DM-V1 Winter Tires