No audio when opening saved AUP file

I have the new M1 macbook pro running Big Sur. Recorded a podcast with a guest and everything looked fine. I saved the project in order to edit it later. After opening the AUP file in Audacity (running 2.4.2) - there’s a flat line, no audio waves. I see that there is a data file stored in the folder and all of those also have flat lines. I don’t see any error messages or anything related.

Please advise on what I can do. There’s no way I can get that guest back again.


everything looked fine.

Did you get blue waves and bouncing sound meters while you were recording?

Recorded a podcast with a guest

How? Describe the conditions and where everybody was. Two people in a conference room or office?

If this was a Zoom interview, it’s still the forum’s recommendation that you get Zoom to record it and ship you sound files. Home techniques may give shaky, bad, or no results.


If you make a simple recording of the MBP’s internal microphone, does that succeed?


I recorded it using the rodecaster. Everything DID record and blue waves were there - I was in the middle of editing and then saved the project to grab lunch and spend time with my daughter. Closed the application thinking the whole project was saved. Then I opened up the saved aup file and that’s where the flat line appeared and all the waves/audio was gone.

I was in the middle of editing

I need to loop you back. Where was the guest? In the room with you? The Podcaster will mix up to four microphones.


offers easy connection to phone

Is that where you got the guest voice from?

You don’t have to record to Audacity.

You can record your podcasts directly to microSD card

Did you do that?


It was not a Zoom call, but an actual phone call. I used the bluetooth option on the Rode Rodester Pro to bring in that audio feed. Once again everything did successfully record and then I saved the aup file - which I guess where maybe the issue be? There is a data folder with a subfolder named “eff” and there are 7 folders labeled d1a to d19, which each folder has tons of AU files. However, all the au files are also flat lined.

No I did not do that. Wish I did because I would recover it from there. Next time for sure I will use a SD card. Any way to recover the audio back? I’m willing to spend whatever including a harddrive deep scan to reconstruct deleted files. The guest is too valuable and a definite lesson learned. Any ideas?

You may have missed two. Once you get the show settled in Audacity, if it’s a mono or stereo track, Export a perfect quality WAV (Microsoft) 16-bit sound file as protection. Then start editing.

We have almost zero experience with the M1 chip and Big Sur. The senior forum elves will want to talk to you. They’re in England where it’s 4AM.

If you never closed Audacity, it should be possible to Edit > UNDO and bring the show back from the cache system. So that may be strike three.

I would start making arrangements of what you would do if the show never came back.


There is another desperation recording method. I assume you had your headphones on? There is a microphone by Olympus that fits in your ear and will record both sides of a conversation. You can plug one of these into an Olympus sound recorder and record the show completely divorced from the computer.

It’s not Warner Brothers Sound Studios, but it’s good for disaster backup.


Definitely will be doing multiple backups. I’ll await for the elves to help. I’m willing to pay any data recovery if I can get this recording back, however there are not that many options for the M1 mac.

I can’t make sense of this - I would have expected at least an error message, and I can’t think of any way that a project could disappear without creating an error at least once.

Perhaps your project’s “AUP” file may provide some insight. Please attach the project “.AUP” file to your reply (See:

Here’s the file.
Ep1.aup (166 KB)

The AUP looks OK.

Do you also have the folder “Ep1_data”?
If so, what is it’s total size?

Here’s all the files associated with it including the AU data files.

Size of that whole data folder with the AU files is 583.5 MB.

As I feared, all of the data blocks are silent. There is no audio data at all, so nothing that can be recovered.

Did you make this recording recently, or is it an older project?

Recorded it yesterday - so less than 24 hours. :cry:

Has the problem occurred before on this machine?
Are you able to reproduce the problem?

Nope. First time. I recorded a test and did the same behavior, made some edits, saved the file, closed audacity completely. Clicked on the file and it’s opening up just fine. However, this is a shorter test file vs a 50 min audio file.

Unfortunately I’ve no idea what might have gone wrong. I’m very puzzled that there was not at least an error message.

Hopefully the problem will never occur again, but it’s worth remembering that computers are fallible (very much so). My top tip is to always export important recordings (immediately after stopping the recording) as a WAV file, so that at least you have a backup of the raw recording (ideally an additional backup copy on another device, such as an external hard drive).

If you get the same or similar problem again, or you have any idea of what may have occurred, please let us know.