It's the same method that oss/commercial drivers use. No hardware
mixing or sound effect - all done by the virtual mixer: sysem-wide 3D
surround enhancement, equalizer, and fidelity (?).
Since most audio chips today don't have these features, it'd be a waste
of resource to support them.
BTW, whoever has problem with the stupid alsa can just use the
oss/commercial driver. It's free and will probably be open-sourced some
time (they mentioned it in v4 doc). Read my wiki if you want to try =>
http://wiki.archlinux.org/index.php/OSS_Commercial_Setup
