Audacity recording over itself?

Hello. Newbie to this forum.

Have been using Audacity since maybe 2005.

Currently, I have a MacBook Pro with macOS Sierra and Audacity 2.2.2

I use Audacity mostly to capture Internet streamingr adio shows.

There was a show that I wanted to listen to this morning, but it was before I planned on getting up, so I set Audacity to start recording the Internet streaming radio station last night before I went to bed. (The idea being that it would still be recording over night and when the show started at 8:00am while I was still sleeping!)

I have done this for over a decade, and as long as you don’t go over 12 hours it seems to work fine.

Well, I only slept for 7 hours last night, and when I got up this morning my show was still streaming, and Audacity was recording it, however the counter showed like 2 hours and 40 some minutes which is impossible?!

At the next commercial break, I saved the file. And then I started up a new file to record the rest of the show.

After the show was over, I went back and listened to the first file/project and the first song I heard was the first sing I started recording last night before bed. (I know this because it was a Rush song that I like and haven’t heard in ages!)

But shortly after this first song played, things got really strange.

Basically the recording reminded me when I was growing up in the 70s and you’d flip through the radio dial to find a song you liked. (Or like the intro to the TV show “WKRP Cincinnati”

There would be a song that would play for maybe 10-30 seconds and then you’d hear a jump to another song that sounde dlike the radio knob being dialed. THis went on and on for about 20 minutes until it was clear that my recording was toast!

My hard-drive is full, but I have like 35GB left, so that shouldn’t cause any issues.

And again, I started recording at about 4:30am and got up at Noon at which time Audacity showed it had been recording for like 2 hr and 40 min

Lastly, I recorded a 2 hour show last night while I was busy listening to another show on another MBP, and that two hour show seems to have recorded okay - listened to the first two songs and they were okay - but now I am paranoid that I cannot trust thi sMacBook Pro and/or Audacity.

What in the world is going on??


Is anyone there?

35 GB out of how much? What is the disk capacity?

I assume that “Sound Activated Recording” is NOT enabled? (In Audacity 2.4.2 the setting is in “Transport menu > Transport Options”)

I have a 1TB internal drive.

Correct, I never turned it on. (And I have Audacity 2.2.2)

While I only have 35GB left, that should be more than enough to record for a while.

Also a little more background…

So I have 3 MacBook Pros. And old one running Mountain Lion and Audacity 2.0.3. This is my best laptop ironically as far as reliability.

Then I have two newer Retina with Sierra on them, and I used to use MBP #2 to record shows also, but them my audio got fubared and so I don’t use Audacity on it now until I can get Loopback and my audio situation straightened out.

Then I have Mac #3 that is a clone of #2, but I was able to get Loopback straightened out on that and it seems to record fine as in no echoes and so on like #2.

I think my issue with #3 - which is what this trhead is about - has something to do with Audacity and maybe storage. I mean the show I recorded doesn’t have any reverb or anything like that, it just feels like I am recording shows on a revolving tape where it records 1-2 minutes then the tape starts over and it records over something that existed previously. Or like I said, mor elike you are changing an analog radio dial every couple minutes.

When I record JUST a 2-hour show, as far as I could tell spot-checking things, that recording was okay.

But when I recroded overnight (i.e. 7-8 hours) all hell broke loose.

Fwiw, 35GB is more than enough to record overnight…

It’s getting a bit low. A 5 hour stereo recording at 44100 Hz sample rate will require about 6 GB. If you normalize the recording, that’s another 6 GB.

What else was your Mac doing overnight? Updating? Backups?

Because this is a “spare” laptop, I just deleted some more files and now have 196GB available.

Nothing. When I recorded last weekend overnight all I had open was VLC and Audacity - that’s it.

And having been an Audacity user since maybe 2005, I have been recording Internet radio station/shows overnight for over a decade with no issues as long as my HDD didn’t fill up. (And if it did, Audacity just quit - I never had the issues I am reporting in my OP.)

It sounds like I have some obscure issue considering no one replied to my OP for over a week, and you aren’t jumping up and down saying, “Oh, you forgot to do ___!”

Why do I always get these bizarre issues?! :question:

One of the shows I record every weekend is “Flashback with Bill St James” which is a 4-hour show.

For some reason, the station I usually record it on started the show early and appears to have cut off some of the show.

So there is another station out West that have the show at 6pm PDT.

And since I have another show I willr ecord on my old Mac, I sure wish I could have some peace-of-mind and know that my Flashback show won’t get botched up again tonight!!

My show starts in 3 hours…

Any other ideas what is happening???

Is your Mac fully updated?
Is it set to update automatically, or even to download updates automatically?

Well, I am running macOS Sierra, so it is not the latest OS, but it is updated as much as it can be.

No, I have it set so I have to manually approve updates…

Have you ever heard of anything remotely close to what I described in my OP?

If you look in the directory Audacity creates, (something like ‘<project_name>_data’), you will see that the sound is saved in small chunks.

The playback you describe sounds like all these chunks have got out of order for some reason.

What is the total size of the Audacity project that is corrupted? How does this compare to the size of previous ones that recorded overnight, that were okay?

The project that I was complaining about is a mere 5.3GB which is tiny compared to things I normally do.

When I went back and listened to this recording that should have been about 8 hours, the first 7-8 minutes sound okay, then when listening to “My Woman from Tokyo” the song sound like the recording is jumping forward every 10-20 seconds.

Is there aw ay to post a snippet here?

Also, when I look in “Sept6_01_data” I see something leling…

First is an “e00” file, and inside that are subfolders from “d00” to “d13” however “d00” says 1:12am and “d13” says 9:17am yet the file is only 2 hours and 44 minutes long?!

So either that 8 hours Audacity should have been recording got written over - as the title of this trhead - or a boatload of files got dropped.

Since the first 7-8 minutes sounded okay, that tells me things didn’t look back to the start and start recording over things, but that somewhere in that 8 hour time-slot over 5 hours of music got dropped…


Is the jumping regular? (For example, jumps on 12 or 18 seconds, but not 13, 14, 15, 16 or 17 seconds.)

I cannot tell by listening, but I can give you a more scientific answer…

If I go into the project folder in FIndr, and go into “d00”, and then sort ascending by “Date Modified”, then I should see the files slowly grow in time, right?

And there should be the same number of files per minute, right?

12:53am - 9 files
12:54am - 30 files
12:55am - 30
12:56am - 30
12:57am - 21
12:58am - 9
12:59am - 9
1:00am - 12
1:01am - 9
1:02am - 9
1:03am - 9
1:04am - 9
1:05am - 9
1:06am - 9

and so on…

About 4 minutes into my recording I start to hear skips around every 6 seconds, and that coincides with the data above going from 30 files per minute to 9 files per minute.

So what is going on?

Also, the very first file is on Sept 6, 2020 @ 12:53am and the last file is Sept 6, 2020 @ 9:16am

That is a time span of 8 hours and 23 minutes, or 503 minutes.

Yet in Audacity, the time shows my recording as roughly 2 hours and 44 minutes in length, or 164 minutes.

Above I was noting that I went from 30 files per minute down to 9 files per minute which is a 70% reduction in files or 30% of the original # of files.

If I take 0.30 * 503 minutes that = 150.9 minutes which is pretty close to the 164 minutes that shows in my timeline.

So it apepars that after the first song I was recording, all of sudden the physical “capture” of my Internet radio stream dropped down to 30% and it also appears that may have “compressed” the recording timeline down from nearly 9 hours down to around 3 hours.

Hopefully that data helps you to help me figure out what is going on…

or a boatload of files got dropped.

That’s my guess. Audacity might do that if the connection was ratty and just stopped dead for periods of time. Audacity might not ring bells or sound alarms. It might just sit and wait for the connection to come back.

Internet connections aren’t a continuous firehose of data. The connections can have collisions, negotiations, traffic-copping, and resends. All that is usually happening so fast that nobody really notices it (usually), but as the connections in your neighborhood get busy, the speed slows down. There is an installer manual page that describes the number of complaints needed to increase the actual neighborhood data service instead of just piling everybody on one connection. Then everything is OK for a while and the cycle starts all over again. My WiFi client list goes to two pages now—and it’s not a dense neighborhood.

You may be experiencing a neighbor (or more) with " New/Superfast Internet Service" marveling at the joys of Wide Screen, HiDef, Adult Entertainment. Not that I would know anything about that.

Find an internet speed tester you like and see if you’re getting anything even close to the speeds you’re paying for. See if your really bad errors hover around certain times of day.


Do you have on-line storage even if you don’t use it? Google Drive or iCloud? Are you sure? Your machine has to keep track of those even though they’re not involved with the show. If a status check fails for any reason, that will cause a system event. Macs don’t like losing their drives.


This could be different where you are.


The connections can have collisions, negotiations, traffic-copping, and resends.

One more. Bad connections don’t have to happen at the telephone pole outside your house. They can have bad connections at the other end, too.

Every so often the Audacity forum (covering multiple continents) will fall apart and I can reach everything else, Google, New York Times, reddit, but not the forum, or it will come and go. Some messages go through and some don’t.


Yes. With default settings it’s one new file per channel every 6 seconds (approx.) and each file is about 1.1 MB.

For a sample rate of 44100, the expected rate of .AU files is 10 per minute mono, 20 per minute stereo.

What’s your sample rate ?
How many channels are you recording?
Are the files (almost) all around 1.1 MB?

Are you using WASAPI in the Device Toolbar?

Sorry for disappearing everyone, but I had to go out of state for a few weeks for my startup, and didn’t have the ability to respond?!

Well, I live on the road using hotel Wi-Fi primarily, BUT I will say this…

If I record my radio shows on my 2009 Mac Book Pro running ancient Mountain Lion and an outdated version of Firefox, I almost never have any issues - and I’ve never ever experienced this issue on my old MBP.

Yet I have two newer Retina MBP’s with macOS Sierra that had ended up having this same issue.

So if it is a bandwidth issue, then I should have the same issue on all three Macs, right?

Ha ha. Or a bunch of lonely travelers watching porn late at night?! :wink:

But again, if this was an Internet connectivity or bandwidth issue, then I would have had this issue with my old Mac Book Pro. And considering that I have been in the same hotel on a long term project for nearly 4 years, and I just started trying to record streaming radio shows on one of my Retinas as I try to migrate off my outdated MBP, it doesn’t seem like its the Internet. (Of course, I’m no telephony or networking expert.)

Can you recommend some test websites?

And what kind of download speeds would I need for streaming Internet radio stations? (I can’t imagine it’s too much?!)

You lost me on this last comment…

No, I don’t do “The Cloud” for security reasons.

AT the time of my OP, I did have a nearly full hard-drive, but I believe I said in a later post that I cleared off nearly all of my HDD - as it was just a clone of my primary rMBP. So now I have a couple or several hundred GBs free.


Okay, so I just ran that test on my old MBP, and got these results…

Ping: 48ms
Download: 1.69 Mbps
Upload: 0.85 Mbps

On my primary Retina MBP - which is technically not the one I was complaining about, but an identical machine - I get these results…

Ping: 44ms
Download: 1.74 Mbps
Upload: 0.86 Mbps

I have no clue what those mean, but again, streaming Internet radio shows are pretty old technology and likely don’t use much bandwidth as far as I know…

44,100 Hz

I believe just two. I am recording in stereo, so there is a left and right channel, I believe.

Spot checked several folders and a couple hundred files and they are all exactly 1.1MB except for one stray one that was 5 KB.

I’m an Apple user and this is an a rMBP running macOS Sierra.