Yes, it makes sense. I measured the time it takes for my function to input data(256 samples). It takes around 16 ms whereas it should be taking like ~6 ms. I do not know why that is the case. This is only true with USB. With the laptop's default audio card it takes ~6 ms. The data comes from the USB's audio capture pin. I have connected a MP3 player to the stereo input of my USB audio device....that's where the input data comes from. May be the input takes more time because USB operation is slow...is that a possibility? Thanks for your help, Pallavi On Wed, Jun 24, 2009 at 9:16 AM, Tim Roberts <timr@xxxxxxxxx> wrote: > Pallavi Joshi wrote: > > > > I think I understand what you mean by data starving and that is what > > is happening in my case. I am not sending multiple buffers. I do not > > have any timer callbacks. I don't know much about them! > > > > I will try and figure out how to do this timer stuff. So I need a > > timer callback to tell my output device that the data is ready to be > > sent? > > > > Thanks a lot for pointing it out. > > As I said, your audio device is a real-time device. The data you send > it are shipped to the speakers immediately. You have to send it 176,400 > bytes every second in order to maintain continuous playback without any > breaks. > > Think about it. Let's say you send 44,100 bytes, then you wait for 1/2 > second. Those 44,100 bytes will finish playing in 1/4 second, then the > board has no more data. The speakers will go silent for the next 1/4 > second. > > How are you generating the data now? Where does the data come from? > > -- > Tim Roberts, timr@xxxxxxxxx > Providenza & Boekelheide, Inc. > > ****************** > > WDMAUDIODEV addresses: > Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx > Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe > Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe > Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx > > URL to WDMAUDIODEV page: > http://www.wdmaudiodev.com/ > > -- Pallavi Joshi (480)-280-2017