Is the sample rate half with the snd read waveform.vi?

Hi Guys,
I plan to use the PC soundcard for data acquiring with the standard LV "snd read waveform" vi. During programming  I found that the sample rate is the half of the adjusted value. For example when I set
  - the format to 8bit mono
  - the buffer size to 11025 byte
  - and the sample rate to 11025
then the operation takes 2000ms. I would expect 1sec.
Used system: LV7.0,  WinXP  SP2.
Does anybody know the reason? I have to use 44100Hz sample rate (44100 "individual" sample per secundum) in my application.
 Thanks,     
    Tomi
Attachments:
Panel.jpg ‏18 KB
Block.jpg ‏15 KB

To be more precise, that's the time take for the below mentioned finite cycle
SI config>> SI start>> SI read >> SI clear.
Its this 'entire' process which takes 1997 milli Sec
Now, what you really have to check is wheather your 'SI read' function is living up to the sampling rate you have set!
Check that by putting your 'time elapsed' check for SI Read function alone!
Hope this helps
Regards
Dev

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