I have '07 premium audio. The noise in the intercom mutes out everything at a volume level of 8 and above. The radio will unmute at 8 but with noise. The noise is related to engine rpm. The static noise increases with engine rpm. Turn off the intercom all noise goes away. Only addition is a Zumo with a mic splitter from Edsets. I have eliminated both microphones. My intercom is almost useless. Anyone know where to look.