I analyzed the GH4 audio buzz issue yesterday. While I couldn't find any issue with the internal mics, the external circuit is picking up camera electronics, primarily the electronic shutter (buzz varies predominantly with shutter speed). I tried a few mics with TS, TRS, and TRRS plugs. The problem is not with the plug itself- the buzz is the same with them all.   If the Panasonic DMW-MS2 with TRRS plug really works without the buzz, then there's something going on with resistance and/or capac