I just tested this myself. I am unable to reproduce it. I even pushed the crash bar up, pressed the buttons on the audio panel, and still nothing. My essential bus avionics turn on with the crash bar up, but no radio static.
Do you have any kind of avionics hardware, scripts, external 3rd party ambient atmospheric add ons, etc... that could be causing this? Anything at all?? No matter how insignificant you might think it is.