[wdmaudiodev] Re: Asynchronous USB Rate Change

  • From: Uwe Kirst <u.kirst@xxxxxx>
  • To: wdmaudiodev@xxxxxxxxxxxxx
  • Date: Wed, 06 Aug 2008 21:14:32 +0200

I guess that you are losing at least one DWORD somewhere, because DWORD allignment is very common to computers. You may not hear if the left and right channel is swapped (4 byte format), but you will hear if the bytes within one channel are corrupted (3 byte format). Luckly the noise goes away as you said, so you have recovered from that error.


/Uwe

Charles Eidsness schrieb:
I still have a lot of testing to do to confirm but I think I've figured this out. I was using a 3-byte 24-bit format, when I change to a 4byte 24-bit format it looks like the noise goes away.

Thanks,
Charles

Charles Eidsness wrote:
Hi All,

I noticed some Async USB related posts on this mailing list, hopefully this is
the right spot to ask this question, if not please let me know.

I'm developing an Asynchronous USB DAC and have run into a problem with Windows XP. About 50% of the time, when Windows changes the sample rate of my DAC I get a 2-3 second long blast of noisy data before Windows starts sending me valid data. I've tried everything I can think of to remove this blast of noise but am running
out of ideas does anyone have any ideas on something I can try?

Thanks!
Charles

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