I guess some hardware might be the issue?
Yes. That’s USB whine. And yes, it’s an interaction between the microphone and the computer.
We tried many different easy ways to get rid of it in hardware and there aren’t any. However, we did design a post production plugin filter specifically for this.
The filter actually removes musical tones from the show. It’s not harmless or magic. So if you have a computer that doesn’t have this problem, use that computer and not the Audacity filter.
There’s data and battery voltage running around inside the USB cable. The computer sends 5 volts up to the microphone to run the electronics and the microphone sends sound data back down to the computer. Lots of microphones work this way. Some news-gathering microphones actually have a little battery inside the microphone to run things since they don’t have a computer available.
The problem comes when the computer 5 volts isn’t “clean.” The computer is going, “It’s too expensive to clean and regulate the 5 volts, so we’ll leave it up to the Microphone.” The Microphone is going, “It’s too expensive to clean and regulate the 5 volts, so we’ll leave it up to the Computer.”
We were able to change the problem (new USB cable, add in-line filters), but never get rid of it. You have to change the computer.
Koz