Most Windows PC's will only have one sound device available. You can check to see if you have additional devices by accessing the "Sounds and Audio Devices" in the control panel of windows (if you have the windows volume icon in your taskbar you can right click that and select "adjust audio properties"). In the Sounds and Audio Devices Properties window select the Audio Tab. The zero index device ID for the sound VI's will be the one listed in the drop down list for the Default device. If you select a different device here, the sound VI's will now use that device for index zero. However, unless you have an additional sound card you will probably only see one device in the list. In that case, putting a device ID into the sound VI's of any value other than zero will not work.
If you have more than one listed you can use this attached VI. In the past I was using a second sound card to do some audio stuff using the sound VI's and I ran into the same questions that you are asking. I also found some VI's that accessed the windows API dll's as I believe you found in one of your other posts. I modified and made my own vi that I'll attach. If you run this VI you can get a list of the names of sound devices that would show up as available sound devices for use in the sound VI. If you run it, the VI will return in an array a list of names of Sound device that you can use. Select the one that you want and pass that index that it is found in the array to the sound VI's provided by NI.
The VI was written in LV 8.0.1 and I don't have access to that version anymore so I can't down convert it for you, sorry.
1. Thank you for your informaiton. Your example vi is very informative for me.
2. In addition to device names, I would like to know where I can find available sound card sampling frequency. As I understand, sound card normally uses 44100, 22050, 11025(?) Hz. I would like to know where I can check or set the values in windows. Moreover, I would like to know if I can check it in Labview.
3. I would like to know what happen in sound card if I use frequency other than 44100, 22050, 11025 and so on. In sound write and wave write vi, I can set any sampling freqeuncy (double value). Do the vis resample? Actually, I experienced that signal is distorted if I save and reroad the signal with wav write vi at 25000Hz. Does it true?
Thank you very much.