[alsa-devel] dmix on hda-intel

[Daniel Chen]

Your controller and codec certainly have dmix, dsnoop, and softvol
enabled by default. However, nothing prevents a rogue application from
grabbing plughw or hw or using OSS emulation (you have the kernel
modules loaded). In other words, inspect the ALSA configurations of
the audio applications that you use. If any of them are not using
"default" as the device, there's a good chance you've located a
culprit.