[PlanetCCRMA] sound issue with webcam

Tom Poe tompoe at fngi.net
Tue Feb 19 14:54:01 2008

Nigel Henry wrote:
> On Tuesday 19 February 2008 17:57, Tom Poe wrote:
>> I'm running FC8, with planetccrma, and have logitech Pro 9000 webcam.  I
>> can record video, but audio is not working.  I tracked the issue this far:
>> "The webcam audio interface must be initialised before the video
>> interface. Linux will by default initialise the video interface first,
>> so you need to remove the uvcvideo.ko module from the /lib/modules
>> subdirectory where it gets loaded automatically, and load it manually
>> after plugging the webcam."
>> Can anyone help me translate this quote into specific steps with
>> commands?  I learn best with really big crayolas.  :)
> Hi Tom. I think you'll need the big crayolas. According to the quote above the 
> uvcvideo is loaded automatically. Assuming that the webcam is a USB one, and 
> the webcam is unplugged, the uvcvideo module would not be loaded as the USB 
> device wasn't present.
> For example. I have a cheapo webcam (ov511 driver). If it's unplugged the 
> ov511 module doesn't load. This webcam doesn't have integrated sound on the 
> USB, but comes with a separate mic/earpiece, with jacks that plug into the 
> soundcard, so the sound is totally distanced from the video, which is on the 
> USB. The ov511 driver is only loaded when I plug the webcam in.
> I've looked on all the kernels on F8, that I have installed, but can't find 
> the uvcvideo module, but I am at this time downloading planetccrma -core. 
> Perhaps this module is on planetccrma's realtime kernel. Time will tell (I'm 
> on dialup).
> Would you plugin the webcam, reboot, then post the output of /sbin/lsmod. Also 
> post the output from:
> cat /proc/asound/cards
> And also the output from /sbin/lsusb.
> I have a usb midi keyboard, and have allways had to add lines for it 
> in /etc/modprobe.conf, as below.
> alias snd-card-1 snd-usb-audio
> options snd-usb-audio index=1
> Otherwise the usb midi keyboard ends up being set as card0, and I have no 
> sounds, which is due to the USB being started early in the boot process, and 
> the keyboard is wrongly detected as an actual soundcard.
> This is presuming that you only have one actual soundcard, and that is set as 
> card0.
>> I've found some stuff on rmmod, lsmod, insmod, modprobe, but just feel
>> overwhelmed.  Any help appreciated.
> I'm guessing here, and wish I had your webcam so that I could try out what I'm 
> going to suggest. By the way the planetccrma kernel is now installed, and has 
> the uvcvideo module available.
> Not having the webcam available doesn't help, but I think the way I'd go about 
> this, is to plug the webcam in, then reboot.
> You say you have video from the webcam working, so the uvcvideo module is 
> presumably loaded, but no sound from the webcam.
> I think now I'd su to root on the command line, and do a rmmod uvcvideo, 
> followed by a rmmod snd-usb-audio.
> I don't like guessing for resolving problems, without having the hardware 
> available, but I'd now do a modprobe snd-usb-audio, followed by a modprobe 
> uvcvideo.
> Sorry if I've been of no help whatsoever, but it's all I can suggest without 
> having the hardware available.
> Nigel.
>> Tom
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Nigel:  Looks like an issue when using ccrma kernel:
# uname -r
I'm going to now reboot to FC8PAE kernel, and try again.

[root@localhost tom]# rmmod uvcvideo
bash: rmmod: command not found
[root@localhost tom]# /sbin/rmmod uvcvideo
ERROR: Module uvcvideo does not exist in /proc/modules
[root@localhost tom]# /sbin/rmmod snd-usb-audio
ERROR: Module snd_usb_audio is in use
[root@localhost tom]# modprobe snd-usb-audio
bash: modprobe: command not found
[root@localhost tom]# /sbin/modprobe snd-usb-audio
[root@localhost tom]# /sbin/modprobe uvcvideo
FATAL: Error inserting uvcvideo 
Invalid module format
[root@localhost tom]#