[alsa-devel] snd_hda_intel shutdown noise

On my HP dv5z whenever shutting down or rebooting there's a loud pop on the speakers just before the screen shuts off. It seems to me that it might be worthwhile to zero the volume or set the mute bit on the output channels just before closing the device. I started looking into this but haven't found the right place to insert the code yet. Anyone else have any ideas? Will this even make a difference?