Hello friends .. 2012 model 308 e hdi (diesel-semi-automatic) I have a car at 32,000km. My vehicle has a humming noise that comes in the range of 50-70 km. This sound is heard when the vehicle is slowing down, not when accelerating. I accelerate with the vehicle and go up to 110-120 km. The sound of a roaring sound is similar to the sound of the voice. They have taken it to the authorized service, they said that it is normal, there is no problem. The vehicle is under warranty until the end of September.