unexpected webcam side effect

[Nigel Henry]

On Friday 06 July 2007 14:16, Tom Horsley wrote:
> Here's some behavior I've never seen before:
>
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=247224
>
> My motherboard's CK804 audio system utterly vanishes
> if I have the webcam plugged in at boot time :-).
>
> Doesn't have anything to do with the highly alpha uvcvideo
> driver I was playing with because I found it fails
> even if the uvcvideo driver isn't installed. Apparently
> it is something about the USB microphone component of
> the webcam that gets linux confused at boot time.
>
> Anyone ever seen a USB device hide a non-USB device like
> this?

I've had problems before with my usb midi keyboard which uses snd-usb-audio. 
often I've had to set options to load it as card 1, otherwise it gets loaded 
as card0, and the soundcard is loaded as card1.

I don't know about your problem specifically, but would you post the output 
from.
cat /proc/asound/cards

First do this booting up with the webcam unplugged, then shutdown, plugin the 
webcam, reboot, and run cat /proc/asound/cards again.

It will be interesting to see if, when the webcam is plugged in, it is being 
detected as card0. ( that is, the usb mike part of it), and your sound card 
is being set as card1.

Can you also post the output of /sbin/lsusb with the webcam plugged in, and 
also the output from /sbin/lsmod.

Nigel.