Random splicing glitch problem


(Audacity 2.4.2)

I’m doing some basic recording and editing with Audacity. I’m recording a script for a lesson over Zoom with a friend. I take the Zoom audio recording (mp4), convert it into mp3 using Quicktime so that I can import it into Audacity. It imports as a mono track so I duplicate it and turn it into a stereo track. Then I reduce background noise and just generate segments of silence between our words and sentences. When I’m done and I’m about to export the file, I check and I see that Audacity has randomly spliced in sounds, sometimes only in the left track, sometimes only in the right, sometimes in both. In certain lessons, it only does it once or twice and I can fix it easily enough and it never offsets the timing for the audio that follows the glitch. In this current one, it did it several times, over longer swaths of audio. (Screenshot attached. Green part is normal, both L and R and the same. Red part is where Audacity randomly spliced in audio from elsewhere in the lesson.)

Would anyone know what the cause of this is and how I can avoid/fix it?

If it matters, I recently switched to a Surface Pro 7 and I don’t remember it happening on my old laptop. Also, since switching laptops, I’ve been getting this Warning-Orphan Block File(s) error message more often when I open a project and I always select “continue without deleting” (screenshot attached.)

Thanks for any help.
Screenshot (16)_LI.jpg
Screenshot (17).png

I don’t know what’s going-on, but a couple of points -

If you install FFmpeg Audacity you can import & export MP4 files (AKA AAC or M4A). With Audio/Video files Audacity will just extract the audio. Download & run [u]ffmpeg-win-2.2.2.exe[/u] and it will install and you’re ready-to-go.

Theoretically you’ll get better quality if you avoid the extra lossy-to-lossy (MP4 to MP3) compression but with a zoom recording you probably won’t notice the difference.

A true-mono file will play through both speakers so there’s no need to make a stereo file (unless you are putting different audio on the left & right sides). If you’ve got a stereo file with silence on one side that can be converted to mono. If left & right are identical It doesn’t make much difference with compressed files, but an uncompressed stereo file is twice the size as a mono file.

Thanks for the reply. I think the place where I eventually upload these audio files requires it to be a stereo track (for whatever reason) and when I tried to upload mono tracks before (for the smaller file size), it wouldn’t accept it. But anyways, I’ll see if that’s still the case.

But yeah, it’s pretty weird. I’ve searched and I don’t think anyone else has come across this issue. I use pretty basic editing functions, I would think. Noise reduction. Generate silence. Cut/paste. Amplify. Change tempo. I have noticed that the glitch happens right after I perform one of these edits. When it happens in an adjacent part, then I see it right away and a quick undo will fix it, then redoing the edit usually doesn’t cause the glitch again. But when it happens in a completely different part of the track, I won’t see it until I check on it at the very end.

with a touchscreen? And you didn’t have one before ?

I had a similar problem a while ago and found that the problem was my filthy :wink: fingers touching the screen and inadvertently changing my mouse selections. :wink:

I hope this helps. :smiley:

Try this (only if you also have a mouse): Enable and disable your touchscreen in Windows 10

I hope this helps. :smiley:

Hmmm, interesting. Yes. Touchscreen, but so was my previous laptop. I use a USB mouse usually, just because it’s easier to manoeuvre than the touchpad when doing lots of editing. I’m not sure if if the touchscreen is the culprit though, as the glitch often happens in a part of the audio file that’s completely off-screen, and hence why I don’t notice it until the end when I review it. At any rate, I’ll give it a try and see if it helps. Thanks.

quick question: where did you find the randomized splicing thingy?

a quick undo will fix it, then redoing the edit usually doesn’t cause the glitch again.

So you can make this problem vanish by Undo > Redo each edit?

I’m not recommending that, but if that works, it would be a terrific clue.