Playback faster than normal

[chinmoy]

I have a creative sound blaster clone sound card installed. Today I installed Audacity 1.3 Beta. When I make a recording and play it back, the playback speed is very fast, and the played back audio runs at a much faster pace producing a highly garbled high pitched sound (Chipmunk effect?). I can hear the sound if I play it back at 0.33X speed. It is not a hardware problem, because recordings made with Windows built-in Sound Recorder play back perfectly. Can anyone please provide a solution for this problem? Thanks a lot.

[Gale Andrews]

It's usually a sample rate mismatch problem, and it typically occurs if you record a track while playing back another one.

The secret is to choose a sample rate to work with in Audacity (that is, the "project rate" bottom left) that is compatible with your sound card. Check your sound card manual for advice about supported rates. Then use that rate everywhere, in each track in Audacity, in any settings in Windows and in the settings for the card. Read this (even if you are not overdubbing tracks):
http://wiki.audacityteam.org/wiki/Troub ... ings#drift

And read this if you are on Windows Vista and 7:
http://wiki.audacityteam.org/wiki/Windo ... d_playback

You may not have correct drivers for the sound card if you are on Vista/7. Please go here to check for latest Creative drivers for your particular card.

If you need more help, please state what version of Windows you are on.



Gale

[chinmoy]

Hi Gale, thanks for your reply. It is not as simple as a sample rate mismatch. Firstly, let me make it clear that I made a very basic test recording, without any other tracks playing back. Secondly, I have tried all the sample rates available in Audacity without any improvement, down to and including 16 bit at 8000Hz. The question of using the same sample rate in ALL the tracks does not arise here, since I am using only ONE track. Also, I would like to mention here that I am using Windows XP, and there are no applications, other than Audacity, running in the background. I hope I have cleared all the pros and cons. And once again I would like to mention that I am using a generic Sound Blaster clone sound card. I downloaded the driver from the net after checking the Creative logo and chip number on the IC (EV-1938). I hope there is no driver issues, since as I have mentioned before, Windows sound recorder is working okay, so I suppose it is a software problem (read Audacity). I would be grateful if you think over this problem and suggest any other solution. Thanks again.

[Gale Andrews]

Hi Gale, thanks for your reply. It is not as simple as a sample rate mismatch. Firstly, let me make it clear that I made a very basic test recording, without any other tracks playing back. Secondly, I have tried all the sample rates available in Audacity without any improvement, down to and including 16 bit at 8000Hz. The question of using the same sample rate in ALL the tracks does not arise here, since I am using only ONE track. Also, I would like to mention here that I am using Windows XP, and there are no applications, other than Audacity, running in the background. I hope I have cleared all the pros and cons. And once again I would like to mention that I am using a generic Sound Blaster clone sound card. I downloaded the driver from the net after checking the Creative logo and chip number on the IC (EV-1938). I hope there is no driver issues, since as I have mentioned before, Windows sound recorder is working okay, so I suppose it is a software problem (read Audacity). I would be grateful if you think over this problem and suggest any other solution. Thanks again.

I don't have much to add. Make sure you obtain 1.3.12 Beta from us (you did not say which exact three-digit version you had). Set the clone as the playback device (as well as recording device) in the Audacity preferences (as the "overdub" troubleshooting page suggests). You need to match rates, not just pick random rates. It's an issue because Windows Sound Recorder does not choose its own rates.

Read the Manual for the clone card and see what rates it supports. Then choose one of those rates in its control panel and that same rate as the Audacity project rate. You could also try the "Windows DirectSound" host in the 1.3.12 Devices Preferences.

Audacity is reiiant on a third-party "PortAudio" Audio I/O interface and any particular version of it may not work well with all devices (especially legacy/cloned ones). I would indeed be susppicious about the card drivers if there is a Creative logo but (I assume) you are not using Creative drivers from the link I gave. I would use the drivers that came on the CD supplied with the device, otherwise contact the support address mentioned in the sound card manual for advice on where to obtain drivers. You could also try 1.3.13 alpha:
http://www.gaclrecords.org.uk/audacity- ... -alpha.zip

which has an updated version of PortAudio, to see if it helps. Be aware in that version that Devices Preferences and Mixer Toolbar have been removed so select device and input in Device Toolbar and be aware that we are still working on this change.



Gale