First 5 seconds of Export buzzing

[TheIrishVeggie]

Hello,

I'm currently running Audacity 2.0.5 on my Mid-2013 13-inch MacBook Air (base model) running OS X Mavericks Version 10.9.1.

I am editing sermons for my church to publish onto the local radio. I used to have an '09 Macbook Pro running OS X 10.8 and ran Audacity 2.0.5 on it with no exporting issues at all. Unfortunately, that computer crashed completely and I've since upgraded to my current Macbook Air in which I've been experiencing issues. With my new laptop, I've been editing sermons that have three separate tracks, that in total exact to a final time of 27:50. Whenever I export the sermon (whether MP3 or WAV), the first 5 seconds of the published file have a crackling sound. I am not certain as to why this keeps happening, but it is quite frustrating and any advice is more than greatly appreciated.

I've tried isolating the problem, but haven't fully figured things out, so here are some other notes that I've observed
-Whenever I install Audacity, usually the first time I export with it, my final MP3 file comes out perfect. Any following times I export, I get the beginning 5 second crackle
-With that said... I've installed 3 different versions of Audacity (2.0.3, 2.0.4 and 2.0.5) with the same issue across the board
-I've exported each individual track separately into MP3 format and had absolutely no issues with them
-I've exported to WAV both before and after installing LAME to observe if the crackling occurred. It still did

In summary, I've come the following conclusion(s): The version of Audacity makes no difference upon the issue, the LAME plug-in is not the culprit of the issue, and lastly I can technically keep installing/deleting Audacity to export my final product, it is just very frustrating as I edit multiple times a week.

So I'm not certain if this is a general incompatibility issue between Audacity and OS X Mavericks 10.9.1, an issue with my files when arranged into multiple tracks (as each exported individually just fine), or something else.

I hope I offered a thorough enough explanation, and do greatly appreciate any advice. Also I have read a similar issue: http://forum.audacityteam.org/viewtopic ... 47&t=73328
but the solutions offered me no help unfortunately.

Thank you for your time,
Ryan

[kozikowski]

Does it happen if you export the first clean show and then export exactly the same show only change one character in the filename?

We're going to want to hear that crackle but you can only upload about two seconds of WAV sample to the forum. Do you have any online file service available?

I don't know about going much further without hearing the problem.

Koz

[kozikowski]

Watch your email.
Koz

[Gale Andrews]

I'm currently running Audacity 2.0.5 on my Mid-2013 13-inch MacBook Air (base model) running OS X Mavericks Version 10.9.1.

Probably not good news - Mavericks and Mac Book Pro seem to have issues with audio.

What playback device are you using - make and model number?

Do you hear the crackling if you play the exported file in iTunes or only if played in Audacity? If only in Audacity, have you tried changing Audio to Buffer in Audacity's Recording Preferences? Try reducing buffer as well as increasing it.

Whenever I install Audacity, usually the first time I export with it, my final MP3 file comes out perfect. Any following times I export, I get the beginning 5 second crackle

That doesn't make much sense unless you are importing the exported MP3 back into Audacity and then exporting that, in which case you will get more loss of quality with every export.

Are the subsequent WAV exports worse than the first one?

Are you making other changes in that project between the first and subsequent exports?

an issue with my files when arranged into multiple tracks (as each exported individually just fine)

Are any or all of the track starting after time zero? If so have you tried selecting all the tracks then Tracks > Mix and Render?

What happens if you open the Audacity Preferences, go to Quality on the left, then under "High-quality conversion", set "Dither" to None?


Gale

[kozikowski]

The poster discovered a work-around when he was arranging to provide much longer sound clips. He prepared some of the work for delivery to me and the problem vanished. I'll cross-post the dialog.
Koz

[kozikowski]

On a first-pass inspection, we know that all Audacity does on Export is add up all your tracks and shovel them out the door. This can give you overload and clipping problems and is the author of the "Normalize Whole Project" project. The real question is why it only happens in the first five seconds.

Turning the right-brain creative side loose: it took five seconds to realize that the sermon was too loud and to reach over and pull the mixer down slightly. If automatic, that's the attack time of the mixer. Koz

[Gale Andrews]

The poster discovered a work-around when he was arranging to provide much longer sound clips.

Which was...?

Or if it was excessive volume from mixing tracks together that are too loud when combined, why does it only happen in the first five seconds and not after that? Or did the poster stop listening after five seconds?

Several other people on Mac have complained about crackling/buzzing/distortion in the first few seconds only, usually caused by not all tracks starting at zero and solved by Mix and Render. Why it only gets reported on Mac I do not know.


Gale

[TheIrishVeggie]

Hello again,

First off, I apologize for my tardiness in response, but I greatly appreciate your help very much! This is an incredible forum overall and again really appreciate the feedback and care.

What playback device are you using - make and model number?
Do you hear the crackling if you play the exported file in iTunes or only if played in Audacity? If only in Audacity, have you tried changing Audio to Buffer in Audacity's Recording Preferences? Try reducing buffer as well as increasing it.

Gale the crackling occurs only in exported format, regardless of my output device. I've listened to my exported MP3 and WAV on my Mac, another Mac and on my iPhone, and it still produced a crackle. Interestingly, when I playback the project for editing directly in Audacity there is no crackle, which again knocked out the possibility of the raw files I was working with being the culprit (and other reported errors with the crackling confirm that).

As for your next question

Are the subsequent WAV exports worse than the first one? Are you making other changes in that project between the first and subsequent exports?

From my experience, no, they're all the same in sound quality and all crackle the same exact way for the first 5 seconds. I am also making no project changes to subsequent exports.

As for what Koz said, my only real workaround (which is still fairly practical) is to just composite all of my separated tracks and arrange them in another project as one uniform track.

Thanks again and feel free to keep asking questions, I hope to be better in my replies.
Ryan

[Gale Andrews]

when I playback the project for editing directly in Audacity there is no crackle

Does the audio of all the tracks start at time zero (0 on the Timeline)?

As for what Koz said, my only real workaround (which is still fairly practical) is to just composite all of my separated tracks and arrange them in another project as one uniform track.

How are you "compositing" them? Do you use Tracks > Mix and Render to do that? If export will cause a crackle, Mix and Render should.

Are all your Quality settings as here?


If not, please give the settings that differ.


Gale

[Jbologna]

I, too, am having the same problem with Audacity on my 13" mid 2013 MacBook Air.

Model Name: MacBook Air
Model Identifier: MacBookAir6,2
Processor Name: Intel Core i7
Processor Speed: 1.7 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache (per Core): 256 KB
L3 Cache: 4 MB
Memory: 8 GB

As an example, the audio from our radio show today--went out live on-air clean. Was clean on the MP3 recording device. When I dumped it into Audacity and exported as MP3, WAV, anything else, for online posting, crackle became audible in first part (and seemingly randomly throughout). But it's not because the audio is maxing out, it seems to be something else. Here's a link to the SoundCloud, where you can hear the crackle in the first 5 seconds. https://soundcloud.com/bunewsservice/bo ... tricks-day

Any assistance would be greatly appreciated (and I apologize if this particular post might not the right place for this).

Jamie