> Matthias Schniedermeyer wrote:
> > man amixer
>
> Thanks. Yes, this indeed seems to map to some functionality that's
> understood by the kernel.
>
> Strange. So does this mean that non-ALSA mixers should not work when
> using ALSA ?
We have emulation layer for non-ALSA mixers. This layer turns mute off
automagically when volume is greater than zero. This layer doesn't work
100%, because ALSA API is more extended and there is no way to map the
extended features to limited API.
> Why do they seem to anyway ?
> Is the driver or hardware side of this mute flag just rarely implemented?
Most of PCI cards which are based on AC97 supports muting for analog i/o.
> Or is the kernel default not always "mute" ?
We mute almost everything. Today, we preset only some of digital controls
and we preserve volume settings for USB devices (might be changed, of
course).
Our policy is: Don't allow to users to jump from skin when default volumes
are invalid. Because we cannot determine the settings of an user amplifier
(analog path), the most safe is mute everything.
Jaroslav
-----
Jaroslav Kysela <perex@suse.cz>
Linux Kernel Sound Maintainer
ALSA Project, SuSE Labs
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