logitech headset != /dev/dsp; mencoder adevice=?
 

I am using a logitech headset on Debian Etch. As such, I dont have a /dev/dsp, which mencoder defaults to for sound capture. Im trying to use this command to capture from my vcr (attached to my rig with a Pinnacle DVC90):
mencoder tv:// -v -tv driver=v4l2:device=/dev/video0:input=0:fps=24:norm=ntsc:amode=1:width=704:height=576 -of avi -sws 9 -vf lavcdeint,denoise3d=4:3:6,scale=512:384 -ovc xvid -xvidencopts bitrate=900 -o ./test.avi

but I segfault with this output:
MEncoder dev-SVN-rUNKNOWN-4.1.2 (C) 2000-2006 MPlayer Team
CPU: AMD Athlon(tm) XP 1600+ (Family: 6, Model: 6, Stepping: 2)
CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 0
Compiled with runtime CPU detection.
Configuration: --prefix=/usr --confdir=/etc/mplayer --datadir=/usr/share/mplayer --enable-xmga --enable-mga --enable-joystick --enable-faad-external --disable-tremor-internal --enable-amr_nb --enable-amr_wb --language=all --enable-largefiles --enable-menu --with-extraincdir=/usr/include/ffmpeg -I./libavformat -I./libswscale -I./libavutil -I./libpostproc -I./libavcodec --enable-radio --disable-libdvdcss-internal --enable-lirc --enable-radio-capture --enable-xvmc --with-xvmclib=XvMCW --enable-fbdev --enable-directfb --enable-win32 --enable-tdfxfb --enable-s3fb --realcodecsdir=/usr/lib/codecs --xanimcodecsdir=/usr/lib/codecs --disable-libavutil --enable-libavutil_so --disable-libavcodec --enable-libavcodec_so --disable-libavformat --enable-libavformat_so --disable-libpostproc --enable-libpostproc_so --extra-libs=-lavcodec -lavutil -lavformat -lpostproc --enable-runtime-cpudetection
init_freetype
Using MMX (with tiny bit MMX2) Optimized OnScreenDisplay
STREAM: [tv] tv://
STREAM: Description: TV Input
STREAM: Author: Benjamin Zores, Albeu
STREAM: Comment:
success: format: 9 data: 0x0 - 0x0
TV file format detected.
Selected driver: v4l2
name: Video 4 Linux 2 input
author: Martin Olschewski <olschewski@zpr.uni-koeln.de>
comment: first try, more to come ;-)
Selected device: Pinnacle Dazzle DVC 90
Capabilites: video capture audio read/write streaming
supported norms: 0 = PAL; 1 = NTSC; 2 = SECAM; 3 = PAL-M;
inputs: 0 = Composite1; 1 = S-Video;
Current input: 0
Format YUYV (16 bits, Packed YUY2): Packed YUY2
Current format: YUYV
v4l2: set format: YVU420
v4l2: set input: 0
Selected norm: ntsc
v4l2: set norm: NTSC
v4l2: set width: 704
v4l2: set height: 576
Selected input hasn't got a tuner!
==> Found video stream: 0
v4l2: get format: YUYV
v4l2: get fps: 29.970030
v4l2: get width: 704
v4l2: get height: 480
Unable to open '/dev/dsp': No such file or directory
v4l2: 0 frames successfully processed, 0 frames dropped.
v4l2: up to 0 video frames buffered.
Segmentation fault

How can I find the right adevice to give mencoder so i can capture sound with my video?

For /dev/dsp you need to load the OSS compatibility driver:
modprobe snd_pcm_oss

ok, after doing that, /dev/dsp exists; however, now the mencoder command I used crashes my rig - i have to push the reset button! So i figure there must be something else i need to do. I can use an adevice= line to change what mencoder uses for sound capture ... what can i say about my audio set up (or anything else) that might help?

Did you run 'alsamixer' or similar tool to set up the headset (headphones, microphone)