It happens to the DPA 4017B and Sanken CS3E. Wrote an email to the lectrosonics and their reply was that it might be the RF leakage is making its way to the microphone through the cable because when I have the butt plug on a long cable and clip the butt plug on belt.. the noise will be gone. They recommended the RF choke adapter MCA-M30 by lectrosonics designed for this purpose. Problem is that I wish not to add load onto the mount if possible. Plus, the adapter only work on certain mics.. hence why I'm looking for alternative solution