Hi
You have to apt-get alsa-base and alsa-utils for all this to work.
alsa-utils is the package which contains utils such as alsaconf.
So apt-get them, run alsaconf as root, check that your mixer
is not muted. ONce alsa has detected and configured your card run :
That will store your settings and will prevent you from doing it all over
again after each reboot.
cheers