Hello Nate,
I used the Sound VIs (Functions >> Graphics and Sound >> Sound) to test what the sound card is doing. Basically, I dropped down a SO Config and wired the error out to a Simple Error handler. When the VI is run, the sound card driver will report an error (the device is already in use) if I try to configure it while it is in operation. You could monitor the Error out, and associate this specific error code with a "busy" sound card in your program.
For the Microphone input volume, I did not see an existing VI that controls this feature. I think that option is controlled by the sound card driver. I am not familiar enough with sound cards to know if this is an option that is programmatically supported. I know that you can achieve this functioanlity with o
ur DSA boards. I recommend that you check with the sound card manufactorer and see if you can call their driver from VB, or C++. If you can, then just compile the code into a DLL, and call the DLL from a Call Library Function inside of labVIEW.
Have a great day!
Joel Andersen
Applications Engineer
www.ni.com/ask
