[SATLUG] USB microphone issue

Bruce Dubbs bruce.dubbs at gmail.com
Fri Nov 11 17:32:50 CST 2011

Igor Gueths wrote:
> Hi all,
> I managed to get to the bottom of this issue after all; as it turned 
> out, I was apparently on the right track as far as the EHCI frame 
> scheduling issue. The main problem is that the bug, introduced around 
> 2.6.39 or so (maybe a bit earlier), causes hub contention when a high 
> speed and full speed USB device are plugged into the same hub; this 
> actually applied to me, since I had completely forgotten my in-built 
> webcam is on the same hub I was trying to use for the microphone.
> IN summary, plugging the microphone into one of the rear ports caused 
> everything to work as expected, vs one of the side ones that I was 
> previously trying to use. Just thought I'd briefly write about this in 
> case someone else down the line runs into what I think is a fairly 
> obscure issue.

Wow, that is an obscure issue.  Good work in figuring it out.

Do you know if the problem is fixed in later kernels?  Linux-3.1.1 was 
just released.

   -- Bruce

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