[pulseaudio-discuss] [SOLVED] usb sound card: PCM has 8 channels, thats too much & cannot submit datapipe for urb 0

[Tanu Kaskinen]

On Mon, 2011-11-21 at 04:19 +0100, David Henningsson wrote:
> On 11/20/2011 11:24 AM, Tanu Kaskinen wrote:
> > AFAIK USB doesn't have enough
> > bandwidth to support uncompressed 8-channel audio,
> 
> Hmm, a long time ago - this was on Windows XP - I remember using a 
> http://www.esi-audio.com/products/gigaportag/ and I don't think we 
> installed any special USB drivers for that.
> 
> 8 channels * 48000 Hz * 16 bit ~ 6 MBit/s, and we're talking about the 
> 12 MBit/s version here, so I guess it should be enough even with some 
> packet overhead, but maybe some of the more broken USB host chips have 
> some problems with it?

Ok, apparently my memory is coming up with random stuff. I have a pretty
strong recollection that there was *some* pretty significant limitation
with what USB 2.0 sound cards can do, and I was pretty sure it was
related to bandwidth. But with max bandwidth of 480 Mbit/s, audio use
cases are pretty trivial...

-- 
Tanu