You can set Audacity to recording your microphone and move it around to see where the noise is coming from. Announce as you go. “This is the Yeti next to the computer.” “This is the Yeti next to the air conditioner.”
If you set Audacity Playthrough to “ON,” you can plug in your headphones and listen as you move the microphone. It shouldn’t take you longer than about ten seconds to find the source of the noise. This test can also tell you if rotating the microphone helps suppress the noise. This works on directional microphones.
I’ve never seen a regular Windows PC that was quiet enough to be in the same room as a sound recording. Even the fancy ones with variable speed vans that “know” how hot the computer is always make residual noises. They’re just not as loud.
It’s possible you’re hearing the background hiss that all microphones have. The only solution is to record closer to the microphone and louder.
You are experiencing several phenomena at the same time.
– USB microphones can’t be separated from the computer by longer than about 6’ (2M). You can get an extension on that by installing a wall-powered USB hub. It’s 6’ to the hub and another 6’ to the computer. That’s 12’ (4M). You can’t plug anything else into the hub. Broadcast microphones and mixers can be separated by hundreds of feet, but they’re much more expensive and tricky to use.
– Even special directional microphones pick up all around the room. You can’t stop them and it’s the reason people still rent and build studios.
http://www.kozco.com/pictures/boothFinished/laptop-mic.jpg
– As a cousin to that, we can’t take out echoes from your voice.
http://kozco.com/tech/audacity/clips/EchoSample.mp3
This person will always sound like she was recording in her mum’s kitchen. Nobody’s going to pay her to do voice-over work like that.
– We can’t take out the dog barking next door. Normal humans automatically “tune out” noises in every day life. I lived on a farm in Upstate New York and people would come up from New York City for a visit and they wouldn’t be able to sleep without the traffic noise that nobody heard until it was gone.
People making their first recording are horrified how loud their apartment/house is.
Koz