Audacity Forum

Whenever I record a second track, I get severe sound problems on play back. The tracks play fine for about 10 seconds, then I get noise, crackles, dropouts...this goes in and out every 10 seconds or so. The noise is on the new track, not on the original one.

I use headphones to hear the first track as I play the second so there is no audio feedback going on. The "Software playthrough" is not checked, only the "Play other tracks while recording new one."

Any suggestions? Thanks!

I assume the track has been recorded badly, but you should export the recorded track as WAV and play it in Windows Media Player to make sure the problem isn't simply that you have not got the computer resources left to play it in Audacity after making the recording.

* Check in the sound device's control panel (or in the Windows System mixer) that you have not got some "noise cancelling" or other effect turned on for the microphone.

* Update your sound device drivers so they are capable of recording and playing back at the same time.

* Make sure you have sufficient computer resources.

Gale

I tried all the advice, problem persists. I even uninstalled my SpyBot software, just in case. I believe I have plenty of systems resources...3 gb of memory, dual processor.

As an experiment, I recorded one track and output to WAV, then played that back on my Windows player through my headphones as I recorded a new track using Audacity. This worked fine (and provides a work-around). Also, if I unselect "play while recording" in Audacity, that also works fine, except of course I can't lay down multiple tracks using this approach.

Does this suggest the problem is within Audacity itself, its ability to play and record at the same time?

Thanks for your help!

westcopy wrote:I tried all the advice, problem persists. I even uninstalled my SpyBot software, just in case. I believe I have plenty of systems resources...3 gb of memory, dual processor.

As an experiment, I recorded one track and output to WAV, then played that back on my Windows player through my headphones as I recorded a new track using Audacity. This worked fine (and provides a work-around). Also, if I unselect "play while recording" in Audacity, that also works fine, except of course I can't lay down multiple tracks using this approach.

Does this suggest the problem is within Audacity itself, its ability to play and record at the same time?

i've never known it work like that, so that playing the track in another player helps - not that we usually suggest it because it seems on the face of it a bit unlikely.

So:

* directly after recording while playing in Media Player works OK, you're saying you repeat the experiment playing the same file in Audacity, with otherwise only that playback track open, and recording does not work?

* What about differences between playback and recording devices? Might you be using the same device for both playback and recording in Audacity (Audio I/O tab of Preferences), but a different one for playback in Media Player (or vice - versa)?

* And what about recording sample rate (bottom left of Audacity) and sample format (Quality tab of Preferences)? Media Player is likely going to record only at 44100 Hz 16-bit. If you are recording at a very high rate (or one that mismatches with the rate of the track you're playing back), either scenario could create problems for the sound device.

So see if recording 44100 Hz 16-bit in Audacity, and experimenting with the recording / playback device choices helps. Note you may not have any device choices apart from Microsoft Sound Mapper, which is only a map to the current system device, not a real device).


Gale

Does Audacity 1.2.6 have "Conversion" settings in the "Quality" tab of preferences (like Audacity 1.3.x)?
If so, then the "Real Time" settings should be set for "Fast Sinc Interpolation" and "Dither"="none".

Thanks for all the help. I'll try to summarize:

Recording quality in Audacity is set to low (16-bit, 1600 Hz)
Fast Sinc Interpolation is set, no Dither
I have one sound device in my computer, Sigma Tel. which came with the system. Drivers fully updated.

By the way, I'm just using the built-in mic as I learn Audacity, new mic is on order. But given my tests, the mic isn't the issue. I have an off-the-shelf Inspiron 1520 laptop from Dell, lots of power and memory.

Here are my results with different scenarios:

1 - Check "Play other tracks while recording", play back first track in Audacity as I record -- Second track has intermittent weird noises
2 - Check "Play other tracks", but mute first track during new record -- Second track has intermittent weird noises
3 - Uncheck "Play other tracks" -- Second track is fine
4 - Play first track through Windows Media Player, record new track in Audacity -- Second track is fine

Note: I have fast sync selected for Real-Time Sample Rate and no Real Time Dither... If I also have High Quality Sample Rate fast sync and no high quality dither, I still have the sound problem, plus the general white noise on the track is horrible.

It may be worth trying Audacity 1.3.6 - it handles the sound card a bit differently from 1.2.x, so it's worth trying to see if you get better performance. No need to uninstall 1.2.x, you can have them both installed at the same time.

(Audacity 1.3.x can open projects made in v.1.2.x, but Audacity 1.2.x can not open projects that have been saved in Audacity 1.3.x).

On first try, 1.3.6 seems to have solved the problem. Thanks!

westcopy wrote:On first try, 1.3.6 seems to have solved the problem. Thanks!

Excellent. Another possible explanation might be that 1.3.6 has a bit more separation of playback and recording threads than 1.2.6, which separation you would of course get if you were playing in a separate application. But I'm still a bit surprised to have not come across this before, given how common Sigmatel inbuilt devices are.


Gale

Gale Andrews wrote:I'm still a bit surprised to have not come across this before, given how common Sigmatel inbuilt devices are.

There have been a lot of miscellaneous driver type problems reported on Vista SP1 and 64 bit Vista that have been fixed as soon as the user switches from Audacity 1.2 to Audacity 1.3
In this case there seems to have been no mention of the operating system - it would be interesting to know if it was Vista.