Hi nunskull I will try to summarize a little bit more with the things that I could identify: Noise have a continuous pattern, sometimes correlates with suspension movements but more audible in lower speeds ( < 55 mile/hour ). But as soon as it starts it continues until the car stops. Noise only appear with AC turned on ( similar on manual or auto mode ). If AC is turned off the noise completly disappear after 15 min more or less. Noise only appear with external tempearture above 28 to 29 degrees The noise stop as soon as the car stops, but still having the engine and AC working ( in a red light for example ) Noise is not affected by higher or lower engine RPM Cannot make an correlation between the AC and suspension neither the service workshop.