Strange popping sound with a stranger solution

Hello,

I recently recorded some clarinet playing using a Zoom H2n portable recorder, which I was using as an external USB mic input for Audacity (2.4.2). After recording, I was disappointed to hear popping and clicking sounds. An example is attached. I realized when I isolated the pop and zoomed in very closely (.63s in the attached sound file), I would find an aberration (see attached image). To fix it, I tried the “repair” effect, which minimized it but it was still there. Then I tried deleting it, and there was still a noticeable sound, as there often is when you delete a sample. So then, I tried deleting it, then cutting and pasting the second half, overlapping it with the first, and fading the two ends (how I usually do audio splicing). Still, there was a sound. The ODD thing is, after all of that (and only after taking all of those steps between the *'s), when I tapped “undo” to get back to the original sample, the aberration was GONE. It fixed itself.

Of course, I tried it with the attached sample, and it didn’t work. It doesn’t matter. My question is, what could have caused this “flat spot” in the first place, and why/how does Audacity seem to be fixing it when I fuss with it? For now, I’m just going to go pop by pop and hopefully get rid of them all, but it would be nice to prevent them in the future.
Screen Shot 2020-07-29 at 6.30.16 PM.png
Screen Shot 2020-07-29 at 6.30.08 PM.png

P.S. deleting the “flat spot” and using “repair” also worked.

what could have caused this “flat spot” in the first place

Forcing a perfectly lovely stand-alone sound recorder into service as a USB microphone.

It could take a handsome amount of time figuring out what in the computer is doing that.

I’ve never tried it this way, but I think you can leave the USB cable connected and change the Zoom from Microphone to Data Transfer. I think the power will still come from the computer so you won’t need batteries. I bet you can record all day long onto the Zoom memory card with no sound damage. Transfer the perfect sound files over to Audacity when you’re done.

Koz

Oh. One more. Your Zoom will look like a drive to the Mac, so you will need to Eject it when you get done and need to disconnect the cable.

I know transferring the files works. That’s how I use my Zoom.

Koz

I put that on my 2-Doo list.

Koz

If you do put the batteries in there, you can record anywhere.

Koz

Do you use iCloud or any other cloud storage? Audacity doesn’t like that very much. All these problems vanish if you record on the Zoom.

Koz

Thanks. Yeah, I had discovered that I never had a problem when I used it on its own. The popping was unpredictable. I probably recorded 2 hours of material in 15 files, but only had pops on 1 or 2 of them. I only did it that way to do faster monitoring and editing in the moment. But I don’t do that often (or when I do it’s in situations where some pops and clicks don’t matter).