Re: [gentoo-user] Still haveing problems with audio and guvcview

[Paul Hartman]

On Fri, Jun 3, 2011 at 1:32 PM,  <meino.cramer@×××.de> wrote:
> cat /proc/asound/cards
>  0 [CameraB404271  ]: USB-Audio - USB Camera-B4.04.27.1
>                      OmniVision Technologies, Inc. USB Camera-B4.04.27.1 at usb-0000:00:12.2-3, high
>  1 [SB             ]: HDA-Intel - HDA ATI SB
>                      HDA ATI SB at 0xfcaf8000 irq 16
>  2 [NVidia         ]: HDA-Intel - HDA NVidia
>                      HDA NVidia at 0xfe97c000 irq 25

(I don't know about Jack or Pulseaudio, in case you use those, maybe
it complicates things) but with ALSA you can specify the cards order
in /etc/modprobe.d/alsa.conf to help this kind of situation become
easier. I have the same (onboard + hdmi + webcam) and it seemed like
the order was random every time I rebooted, and I had to reconfigure
all my things that use sound. Fixing the order to be the same every
time helped to solve that problem.

For mplayer you can force the output to use the proper device in your
mplayer.conf

Use alsamixer to enable/disable the inputs depending on when you are
using them. Maybe your microphone is recording and played back when
you watch TV, causing the bad sounds... it's only a guess. :)

For testing it might be easier to use aplay and arecord (from
media-sound/alsa-utils) since they give you a more explicit choice of
ALSA devices. For example "aplay -l" will list your playback devices,
"arecord -l" will list the input devices. Then you can experiment with
them and alsamixer until you find which one works.

The alsa-info script will give you all the info about your sound
hardware. Probably more info than you care about knowing. :)

Good luck,
Paul