Hum occurs when I hit RECORD [SOLVED]

I’ve been attempting to track down an electronic hum that has been occurring. After switching out mics, and channels on my mixer, etc. and still hearing it…I now realize it begins when I hit the RECORD button in Audacity.


What to do?
Any help is appreciated.

Windows 10, Audacity 2.1.0, Obtained from .exe installer (I think)

Instead of hitting Record, right-click the recording meters > Start Monitoring. Same thing? This little dance opens up all the sound channels as if Audacity was going into record, it just doesn’t go. If the hum is still there, this can be useful for troubleshooting. You can hunt and inspect all day long without running out of recording space.

You will only hear something if Audacity > Edit > Preferences > Recording is set to Playthrough. We assume you’re on headphones for all this. Running speakers and microphones in the same room is not a good idea.

Also remember if you unplug a USB sound device, it will vanish from Audacity even if you plug it in again. Restart Audacity or Transport > Rescan…


Thanks Koz.

No luck yet.
First step was completely powering down my computer. No change.
Rescanned all audio devices. No change.
Right-clicked to monitor…rather than hitting RECORD…produces the same humming result.

The humming occurs no matter which set of headphones I use, which mic, and whichever channel.

I am going to attempt to remove audacity from my computer and completely reinstall it. Ugh.

Any other suggestions would be great.

Uninstalling and reinstalling did not solve.

Hitting RECORD causes a Hum in the headphones. If I’m just recording on my machine, Audacity does not capture the Hum. But if I’m also using Google Hangouts etc. then the Hum is picked up.


I am going to attempt to remove audacity from my computer and completely reinstall it. Ugh.

I don’t know reinstalling is a good idea. If you hang something up, you may then have two problems instead of only one.

Export a 10 second Stereo WAV or 20 second mono WAV of the hum. Say a few words to give us an idea of what “normal” is.

Post it here on the forum. Scroll down from a forum text window > Upload attachment > Browse.


Dueling posts.
I’m going back to read that.

If I’m just recording on my machine

Recording what on your machine?

Google Hangouts etc.

What’s etc? Audacity doesn’t much like interacting with internet services. We recommend specialty software to record Skype, Games, etc.

Hangouts bring conversations to life with photos, emoji, and even group video calls for free. Connect with friends across computers, Android, and Apple devices.

I think the chance of getting Audacity to work with that is zero, if that’s what you’re trying to do.


That isn’t usually the case on Windows, though I see it happening on Mac.

PortAudio look likely to implement hotplug support at long last, so we will have to see next time we update PortAudio.


So I think we can mark this as solved. The hum occurs, when I hit RECORD. Yes. But it actually comes from Channel 3…which is the input from my Laptop to my Mixer. (An 8-channel Behringer with USB). However, it only shows up when the level of Channel 3 is set higher than the level of channel 1…which is my in-studio preamp mic.

So as long as I keep channel 3 even a hair below that of channel 1, I’m good.

Thanks for all the help. :smiley: