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It may be the case that you may hear some unwanted noise while playing back with 24/32 bit. This is a problem in the USB system. Explanation from Hans Petter Selasky: ---snip--- The current USB sound driver only uses one isochronous buffer, that is restarted when it is completed. This will lead to a short period of time, +1ms, where no sound data is sent to the external USB device. Depending on the load of your computer, this can be as much as 50ms. So the USB sound driver must use 2 isochronous transfers. At the beginning one will queue both. Then these are restarted on completion. This will result in a constant-rate data stream to the external sound device, a minimum sound buffer equal to the size of the isochronous buffer, and possibly the sound will reach your ears with less delay. Little delay is a result of constant data rate. Currently only my USB driver will support that. If one tries that with the USB driver in *BSD, then it will crash at the first moment one gets a buffer underrun. ---snip--- Submitted by: Kazuhito HONDA <kazuhito@ph.noda.tus.ac.jp> Mono-recording still not tested by: julian |
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| uaudio.c | ||
| uaudio.h | ||
| uaudio_pcm.c | ||
| uaudioreg.h | ||