Recorded audio sounds slow

[dfbarbour]

Are the recorded tracks the same length irrespective of whether they play back correctly or too slow? Or is the slow track longer than it should be for the length that you recorded?

Slow track:
One minute (1:00) of stream = approx. 1:06 Audacity recording

When playback is correct:
1:00 = 1:00

Here are some interesting twists:

1. YouTube (Flash) streams now always seem to record correctly, although I have had problems with other Flash streams in the past.
2. When a Firefox tab is open containing a YouTube video I have played from, the tab which contains the problem (Vimeo) stream now records correctly.
3. When recording a Vimeo stream, Edit > Undo Record fails to remove the track as it ordinarily does after a single take.
4. After running Tracks > Remove Tracks after a slow Vimeo take, recording returns to normal speed, however, Edit > Undo Record still fails to remove the track.

The problem seems to be with Vimeo. Here is an example of the problem video: http://www.premrawat.com/category/updates/

A workaround is: 1. Record a slow take, 2. Tracks > Remove Tracks, 3. start recording and restart the stream. (However, Edit > Undo Record still fails to remove the track.)

[dfbarbour]

Have you tried setting Audacity to record in stereo?

Recording in stereo has no effect, i.e., slow recording persists.

[Gale Andrews]

Are the recorded tracks the same length irrespective of whether they play back correctly or too slow? Or is the slow track longer than it should be for the length that you recorded?

Slow track:
One minute (1:00) of stream = approx. 1:06 Audacity recording

When playback is correct:
1:00 = 1:00

OK so it is a recording problem presumably when the playback rate of the video differs. If so you will never be able to predict it in advance.

Steve has suggested before that pulseaudio volume control should take care of these problems but he would have to advise you how to configure it to do this.

The obvious solution is to download the videos ( https://vimeo.com/help/faq/sharing-vide ... ing-videos ) or unofficial solutions (see Google).

A workaround is: 1. Record a slow take, 2. Tracks > Remove Tracks, 3. start recording and restart the stream. (However, Edit > Undo Record still fails to remove the track.)

I have no idea how you managed to do that. What menu item or button do you use to record?


Gale

[dfbarbour]

What menu item or button do you use to record?

I click on the Record button (red circle button)

Update:
My workaround did not work today. However, I discovered another possible workaround:
1. Open a Firefox tab and play a YouTube (Flash) video. Leave the tab open.
2. Go to the Firefox tab that contains the Vimeo video. Play the Vimeo stream and record the audio normally with Audacity.

For some reason, if a Flash video was previously playing in another Firefox tab, and the tab is left open, Audacity will then record at the correct speed from the Vimeo stream.

The obvious solution is to download the videos ( https://vimeo.com/help/faq/sharing-vide ... ing-videos )

This is not an option. The Vimeo player on the site I am trying to record the audio from does not have a download button. (http://www.premrawat.com/category/updates/)

[steve]

Audacity > Edit > Preferences > Quality
Default Sample Rate: 44100
Default Sample Format: 32-bit float
Real Time Conversion
Sample Rate Converter: High Quality
Dither: None
High Quality Conversion
Sample Rate Converter: High Quality
Dither: Shaped

This will probably not solve the problem, but the first thing that I would do would be to set "Real Time Conversion > Sample Rate Converter: Medium Quality".
Since Audacity's resampling library was updated, even "Medium Quality" is very good, and going down from "High Quality" to "Medium" is a lot less demanding on your computer. This will not adversely effect the quality of the recording, it just slightly reduces the resampling quality if Audacity needs to convert sample rates on the fly. Exporting and mixing down use the High Quality Conversion settings.

Regarding the problem, this does not sound like an Audacity problem. I think it is almost certainly somewhere between Firefox, whatever plug-in is playing the media, and PulseAudio.

A common issue when playing media in a web browser (though not generally a "problem") is that the ports into PulseAudio are not closed properly when the video stops. I suspect that this is related to the problem that you are experiencing. The change in speed and pitch (with no mention of stuttering or rapid clicking) does sound like a sample rate mismatch.

If, as I suspect, the problem is in this area, then we are probably not going to be able to "fix" this problem but hopefully find a practical "solution" (aka "workaround").

This is not an option. The Vimeo player on the site I am trying to record the audio from does not have a download button.

That's probably because the copyright holder does not want you to copy it.
Nevertheless, assuming that you have obtained the legal rights to copy this content, I find that "FlashGot" (not to be confused with "FlashGet") Firefox plug-in works with most on-line video content.

[Gale Andrews]

My workaround did not work today. However, I discovered another possible workaround:
1. Open a Firefox tab and play a YouTube (Flash) video. Leave the tab open.
2. Go to the Firefox tab that contains the Vimeo video. Play the Vimeo stream and record the audio normally with Audacity.

For some reason, if a Flash video was previously playing in another Firefox tab, and the tab is left open, Audacity will then record at the correct speed from the Vimeo stream.

That is possible - I understand Firefox uses Flash for Vimeo videos.

It's also possible that if the previously playing video played at the wrong speed then the Vimeo stream loaded in the same tab would record at the wrong speed.

Or... it all depends on the original video.

Is your Firefox Flash plug-in up-to-date?

Another thing you could try is use a browser that uses HTML5 for Vimeo videos instead of Flash.

The obvious solution is to download the videos ( https://vimeo.com/help/faq/sharing-vide ... ing-videos )

This is not an option. The Vimeo player on the site I am trying to record the audio from does not have a download button. (http://www.premrawat.com/category/updates/)

Of course it's an option. I can download any Vimeo video at will - download button or not. Use your favourite search engine for unofficial solutions, or try Steve's suggestion.


Gale

[dfbarbour]

Thanks, Gale and Steve!

[gbell12]

For any future Googlers...

The workaround is to record at 44.1 kHz (Project rate 44100 in the lower left of the window, then start recording).

The resulting track will be at 44.1 kHz. Use the little pulldown on the track next to the text "Audio Track", then Set Rate, then set the rate to 48.0 kHz.

Playback and resulting exported MP3 file will be the correct pitch/speed.

This is for Audacity 2.0.5 on Ubuntu 14.04.1 with Pulseaudio active and working, but the "Audio Host" in Audacity set to ALSA, recording something playing back in Firefox.

[rebelwriteruk]

I'd Like to thank gbell12 for the workaround, it's certainly cured my frustrations, this happened every time I recorded anything be it a radio stream, voice recording, or a file on my hdd. Everything was recording at around 10% quicker resulting in around a 10% slower playback, I even resorted to running Audacity in wine (which actually recorded fine) but the trade off was I had to save as .wav then open the file in my native Audacity version to convert into my preferred file format. so thanks yet again to gbell12 for the workaround

[Gale Andrews]

I'd Like to thank gbell12 for the workaround, it's certainly cured my frustrations, this happened every time I recorded anything be it a radio stream, voice recording, or a file on my hdd. Everything was recording at around 10% quicker resulting in around a 10% slower playback, I even resorted to running Audacity in wine (which actually recorded fine) but the trade off was I had to save as .wav then open the file in my native Audacity version to convert into my preferred file format. so thanks yet again to gbell12 for the workaround

Yes thanks to gbell12 indeed for contributing.

However do note that the solution of changing project rate is not foolproof and has just as often been reported not to work (or only to work sometimes) which is probably why none of us mentioned it.

Assuming you are choosing the pulse device to record from in Audacity, pulse should be able to handle the conversions without speed changes. But if that handling does not work and for example you have a 44100 Hz only device and the stream is 48000 Hz, you may see the problem you describe.


Gale