Hello;
the CMI8738 allows for 4 channel output by providing a second DAC, but sadly the hardware has no volume control for said second DAC.
A review of /usr/share/alsa/cards/CMI8738-MC6.conf shows that the implementor of said file was aware of the need to fix the problem:
# 2nd DAC # FIXME: we need a volume attenuator for rear channel. CMI8738-MC6.pcm.rear.0 { @args [ CARD ] @args.CARD { type string } type hw card $CARD device 1 }
I'd really like to fix this!
Is it fixable by creating a softvol plugin?
http://www.alsa-project.org/alsa-doc/alsa-lib/pcm_plugins.html#pcm_plugins
if so, can i have a hint? :-)
so, if i have to invoke speaker test with -Dhw:0,1 to get 4 channel out, what does that tell me about how i need to configure a softvol for this item?
Or am i missing the point and it's actually the *driver* that needs to be doctored up to provide a softvol implementation. If so, how?
tnx!
johnu