Re: [LAU] Issues with JACK - Linux-audio-user

5 Mar 2013

On Tue, 2013-03-05 at 08:45 -0800, Gabriel Beddingfield wrote:
...
  On Mon, Mar 4, 2013 at 3:26 AM, Gabbe Nord
&lt;gabbe.nord(a)gmail.com&gt; wrote:
  Hmm, alarming! I do use both USB keyboard and USB
mouse. My soundcard is
 also USB. I do have alot of other devices plugged in aswell to my USB. Is
 there any way I can fix this, other then getting "real" plugs for the USB
 keyboard/mouse? Like I said, there's still a couple of devices that uses USB
 even if I get rid of the mouse/keyboard.  
 USB devices are allowed to reserve bandwidth... and that affects every
 device attached to the same USB hub.  Now, you might say, "I don't use
 a USB hub" -- but that's not true.  Your PC has one or two USB hubs
 that it uses internally.  In my case, I had a USB audio device on the
 same hub as a USB Webcam.  Even when I wasn't using the Webcam, it was
 reserving bandwidth.  Thing would be running fine, then all the sudden
 audio comes crashing down with an xrun.

 For me the PC had two internal hubs.  I used a different USB port
 (attached to the non-webcam-hub) and the problem was solved.

 I'm not saying this is your problem... but use something like 'sudo
 lsusb -t' and inspect which devices are connected to which hubs.
 Unplug as much as you can.  Try different ports. 
Slot plates for using the USB ports provided by the mobo do cost around
EUR 2 only.
FWIW it's possible to unbind USB devices, assumed an unneeded port
should share the IRQ with something that is important.