> 
> I got it working with MPlayer.  Before trying mplayer, I tried alsamixer,
> but wasn't able to figure out how to fix things with that.
>

Those are two separate things. ALSAmixer controls the output/input channels
of the ALSA chaining. MPlayer attaches to one of the ALSA channels and pushes
data through, but does not work at the hardware level (unless its codec does).

Regardless, I am glad the suggestion worked for you. MPlayer and MEncoder are
some of the best open-source software (OSS) I have ever used. I love so many
things about MPlayer, and where do I start... The fact that you can do all
kinds of filtering, cropping, rotating of the output is great. The fact that
you can perform format conversion, dictate frame-dropping, dictate the codec to
use, etc,... great. But the greatest power of MPlayer (in this guy's opinion)
is when you drive it from a filesystem pipe and have it operate like a blackbox
behind your own software. I do that for still image extraction, etc. Waaaaaay
too useful to go un-mentioned.