Couple interesting videos about the noise:
https://www.youtube.com/watch?v=3dUjmYTB060
What's up with this video? They claim that a "sescom cable" is the only way to eliminate the noise... I gather that any attenuator would work to keep the camera's mic level from overloading, but they just keep calling it THE AMAZING MAGICAL MIRACULOUS WONDERFUL SESCOM CABLE or some crap... WTH?
yeah, audio snake oil cable! Too bad he didn't explain what it does.