I have the Panasonic Lumix G2 with a shenggu 108 external microphone and the 14-40mm lens. So i keep getting this buzzing/staticy sound when ever i record video. It's quiet when i do not use my external microphone but when i do it's extremely loud and you can't hear much of anything but the static. I don't think it's the AF on the lens because i turned that off and i still got the noise. Someone help please.