Definitely mplayer is a better program than zinf. Actually, I came across another .asoundrc or asound.conf configuration, done for the Intel with an 845 chip, so not quite the same as mine, that does use dmix and also works for me. It is at http://www.alsa-project.org/alsa-doc/doc-php/template.php?module=intel8x0 Also a dmix howto: http://alsa.opensrc.org/index.php?page=Dmix-plugin
