i have tried to use loop with timer to take the data for 1 second period .but it will show the error
is there any other method to perform this function ?
You are on the correct track here using a while loop and reading data in say 1 seconds interval. But try to skip the timer. Let the sound card do the timing details for you. Also use a larger buffer size for the sound card. You set the buffer size by the "number of samples/ch" control in the Sound Input Configure VI. Set this value to be at least 2 to 5 times larger than the "number of samples/ch" value used in the Sound Input Read VI. My guess is that you have a sound card buffer overflow problem.
Besideswhich, myopinionisthatExpressVIsCarthagemustbedestroyeddeleted (Sorry no Labview "brag list" so far)