I do not have your code so I am guessing...
I recommend putting your code to run the sound file in a parallel loop to your data acquisition loop. When you want it to play, you set a notification in the daq loop and it allows the sound loop to run. Surf the user manual and shipping examples for instructions on notifiers.
If you still see the daq pause, consider increasing your buffer size. My last suggestion is to put the code to run the sound in a subVI and change it's execution system so that it will run in its own thread. There is a shipping document called LabVIEW performance and memory management that discusses this in more detail . You can find it by opening LabVIEW >> help >> search the labview bookshelf.
In the end, you may not be able t
o get both devices--sound card, daq card--to work well at the same time. Both are processor and resource hogs.
