Loud hum while recording

I recently downloaded Audacity 2.1.2 for Windows. My operating system is Windows Vista and the external microphone I’m using is Audio-Technica ATR2100-USB. I have a loud hum on all my recordings that none of the filters will eliminate. Also, I’ve checked to make sure that it’s not the microphone itself. I have also checked to make sure it’s not a ground loop issue. I get the loud hum on both my desktop computer running Windows Vista and my laptop running Windows 10 whether it’s running on the power supply or solely on the battery. Also, I’ve gone to other locations in my home with my laptop with the same hum. I’ve tried hand holding the mike or from its stand with the same result. Does anyone have a solution to this type of problem?

I’ve checked to make sure that it’s not the microphone itself.

By doing what? The headphone jack only checks about the first 2/3 of the microphone. It’s almost certain it doesn’t decode the bitstream.

Post a sample of the hum. Drag-select 10 seconds of stereo or 20 seconds of mono, export WAV (Microsoft) 16-bit and post it here. Scroll down from a forum window > Upload attachment.

Chances are good you don’t have a normal problem. You checked everything on my list. So now we’re in the magic zone of two or more problems, or an error that sounds like hum.

Has the microphone ever worked? Did you buy it new?


Thanks for responding to my problem. When I go to export a WAV 16-bit recording I keep getting the message the file is too big, maximum allowed size is 2 MiB. Even when I reduced the length of the mono recording to 1 second, I still received this message. I’m very new to Audacity so I must be doing something wrong. As far as the microphone I bought it new through Amazon and even sent the first one back. I’m still receiving this loud hum on my playback with this 2nd one.

Are you exporting the sound file to your desktop? We have to start from somewhere, so do that. Drag-select ten seconds or make a ten second recording. Remember when you drag-select a portion of the show, you need to use File > Export Selected, not File > Export.

Before you send it to the forum, Right-Click the file > Properties and a panel should open telling you how big Windows thinks the file is.



While I was waiting for your reply I found a way to eliminate that hum from the playback of the recording through the Noise Reduction effect feature. So for the time being I’m happy with that solution. Thank you for taking the time to converse with me.

Best regards,

Noise Reduction isn’t free. It’s adjusted so it damages the bad sound more than the good, but it always damages both.


If you select 1 second of the audio you have to chose “export selected audio”, rather than “export audio” as the latter will save the entire track, not just the selected [1 second] section.

I have this same microphone, and I can say with certainty… it’s the microphone, or more specifically the microphone’s orientation. I don’t know whether it’s where the microphone’s “front” is facing or its “back”, but if I place this microphone in the position that makes the most sense at my desk, there is a pronounced 60Hz hum. If I move the mic so that it is beside me, aimed perpendicular to my monitors, the hum goes away. It could be shielding at the back picking up emissions from the monitors, or whether it’s picking up the fluorescent lights in the room behind me, but it’s definitely picking up something.

I used this same mic to record some screencasts last year, when my desk was IN the room that is now behind me, so I would think if it was the lights in there, it would have been a problem at the time. Also, I had the same monitors and the same relative positioning between them and the mic, and I didn’t have any of these problems at that time.

It’s clearly an electrical shielding problem of some kind. Try re-positioning the mic and see which position eliminates the noise. Unfortunately, it may not be the angle you wanted.

You can go hum trolling. That’s how I did it. Move the microphone around announcing as you go and make recordings. I had one badly made LED desk lamp which put out a quiet, odd hum/buzz along with the light. The more notable one is the bass music cabinet which didn’t go off when I turned it off and emitted a very low volume hum all the time.

And last is the very well behaved sound mixer whose power supply brick induced hum a foot (.3M) in all directions. All those were found by moving the microphone back and forth and aiming it (directional microphones) around the room.