Got Buzz? Got Hum?
Hi, this is a copy form another post, but the info can really help you solve problems and come back with the good stuff.
Try connecting the same gear at home the same way you did when you were getting the problem (assumedly elsewhere). If it still makes the same sound, try another mic because it could be the mic itself or the mic cable.
I have some "special" cables that are more resistant to noise than bargain brand XLR cables. There are some new Neutrik XLR connectors with built in protection. They are a bit finnicky to wire, but reports have come back that they are working.
Was your camera on battery or AC? If on battery, it's not a ground loop.
If on AC, was any sort of other cable attached to the camera? Video cable attached to a video monitor that was plugged in to another AC outlet. That could create a ground loop.
Nearby fixtures, DIMMERS ESPECIALLY, can radiate buzz into your audio, no attachment necessary. Including nearby residential recessed fixtures on wall dimmers and the ubiquitous torchiere floor lamps. Either turn 'em all the way up or turn 'em off. Even residential dimmers in ANOTHER PART OF THE BUILDING can put noise into your audio.
Some "high-tech" industrial, wall-mounted office lighting controls in hotels and convention centers also radiate noise through the air that will get into audio.
The mic cable being parallel to an AC cable can induce hum into the audio.
I THINK your best defense is to have mic cables with really good shields and the shields connected to the shells of the XLR connectors with those new XLR connectors. There are a few applications, like connecting two pieces of SOME powered gear, where these cables may actually cause problems. So mark them so you remember they are your bullet-proof mic cables.
That's my story and I'm stickin' to it!
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