Running openni_camera and an additional external USB camera

edit

I would gess that this is caused by the high data amount of both devices. The Data is to much for one single USB-Bus (not ports). Try to check which bus the devices are connectet to by $lsusb . Then simply try to connect the devices to different buses. Another idea would be that the webcam is claiming the hole bandwith of to USB-port. Webcams request a whole load of bandwidth, usually more than they need. The uvcvideo kernel module can be set to ignore the requested bandwidth, and to calculate the right bandwidth. Try:

$sudo rmmod uvcvideo
$sudo modprobe uvcvideo quirks=128

This will be reset every reboot. If this works, create the following file:

$sudo vi /etc/modprobe.d/uvcvideo.conf

containing the line:

options uvcvideo quirks=128

reference:
http://comments.gmane.org/gmane.linux.drivers.uvc.devel/5510

https://www.linuxquestions.org/questions/linux-kernel-70/facecam-312-kernel-10-10-conflagration-help-853934/