Flatline tracks – Audacity 2.3.3 on Os X 10.15.6

Hi everyone,

I fear the worst but thought it would be worth checking here.

I have been working on a podcast for a few days, comprising around 30 tracks – some edited with effects.

I opened up the file to do some voiceover work this evening, plugged in my mic via Duet USB interface and pressed record. No output recorded. I removed the usb and I think that’s where my Macbook Air crashed, I can’t remember if I forced quit or chose quit in Audacity. I went back in to have another try after checking I had selected the correct input source. But the same thing kept happening.

Here is where I may have stumbled, according to a few posts on the forum.

I was given the option to recover, which I took.

I reopened the aup file and discovered that all the tracks had now flatlined. No sound.

To make things even more confusing, I went into application support and discovered that autosave folder is empty and session data folder only contains “audacity-lock-apple”.

Aup file remains on desktop as it always has, together with the data files (in a folder that’s 2GB in size). Individual project tracks remain in the same place as when I started.

Is this project written over and irrecoverable?

Crash report and audacity log attached.


Audacity_2020-10-15-182042_Amars-MacBook-Air.crash (94.7 KB)
duetUSBDaemon_2020-10-15-181551_Amars-MacBook-Air.crash (42.5 KB)

I’d suggest that you make a backup copy of those before doing anything else - it may not be possible to rescue the project, but we can try.

I would also suggest updating Audacity to the current 2.4.2 version: Audacity ® | Download for Mac OS

Please attach the .AUP file to your reply.

Ah thanks a lot Steve. Willing to try!

ML_Oct 2019.aup (617 KB)

There’s no obvious problems with that file. It appears to have a little over thirty tracks, and the XML is valid.

When you’ve updated Audacity, try opening ML_Oct 2019.aup from “File menu > Open”. Make a careful note of any error messages that occur.

No error messages as such. Just this one about orphan block files, which I’ve seen several times.

Tracks all still flat lines.
Screenshot 2020-10-17 at 14.32.26.png

The warning message says “5” orphan files, yet you previously wrote that the _data folder is “2GB in size”.

I don’t know how this happened, but I’m guessing that most (or all) of the .AU files in the “ML_Oct 2019_data” folder are silent. If that’s the case then there’s definitely no possibility of recovery. Try dragging a few of those .AU files into an empty Audacity project and see if they are silent. (If they are not silent, be careful not to modify the files in any way).

There has been a lot of work in recent versions of Audacity to make projects more robust, so hopefully this problem will not occur again, but for important work I would highly recommend using
“File menu > Save Project > Save Lossless Copy of Project”
to create backups periodically while you work.

Yes, they’re all silent. I’m just going to start again and keep saving. Thanks for your help.

Tip: With important jobs I will use a naming scheme to create a series of backup “restore points” (using “Save Project As…”)


This requires a lot of disk space, but it’s a life saver if anything goes wrong.

Got it. Cheers.