Hi fellas, I just picked up my 99 GS400 this week, the car meets my expectation and more, however, while I was listening to the radio and CD, on 2 occasions I heard noise came from front door speakers that sounded like distorted MP3s, what do you guys suggest to look first?? I really enjoy the stock system, but its really weird for a car this class to have distortion like this.

btw, the car is a 99 with Nakamichi system.

 

does the noise only appear when playing cd's? does the distortion come from all speakers?