Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: Floor Mat
We recommend the use of Genuine Mazda floor mats. WARNING Make sure the floor mats are hooked on the retention pins to prevent them from bunching up under the foot pedals: Using a floor mat that is not secured is dangerous as it will interfere with the accelerator and brake pedal operation, ...

Mazda 6 Service Manual: Distance Recognition Support System (DRSS) (Some models)
The Distance Recognition Support System (DRSS) measures the distance between your vehicle and a vehicle ahead using a radar sensor (front) while the vehicle speed is about 30 km/h (19 mph) or faster, and if your vehicle approaches a vehicle ahead more closely than what is appropriate for maint ...