The RNS-E goes into standby when you unlock the car, and standby powers on the amp qnd other peripherals. The Bose amp is know to cause that white noise, some more, some less. With the Symphony the amp got turned on with the radio (or ignition when the radio was on) and therefore you didn't hear that noise that much. In my B6 I hear this with both the Symphony (when volume was off) and the RNS-E (standby or volume off).