[Alsa-user] softvol volume control unresponsive

[<fre...@of...>]

Dear ALSA,

I'm not really having a great deal of luck getting responses from ALSA
developers here, but I figured I'd try again just for the sake of
documenting the various bugs that I've been running into. I guess most
people have moved to Pulseaudio and that is why ALSA development has
petered out? Which is a bit sad because it seems like ALSA has a lot
of potential.

Anyway I have a setup which combines various cards and usually it
works fine, but sometimes when I restart I find that one or both of
the softvol controls I set up fails to work, in other words I cannot
change the value in 'alsamixer', and when I use 'amixer' to change it
then I get "Invalid command!". Any ideas how I can make the control be
responsive again?

    $ amixer -Dmusic controls       
    ...
    numid=12,iface=MIXER,name='Music'
    ...
    numid=11,iface=MIXER,name='Noise'
    ...
    $ amixer -Dmusic set Noise '5%-'
    Simple mixer control 'Noise',0
      Capabilities: volume
      Playback channels: Front Left - Front Right
      Capture channels: Front Left - Front Right
      Limits: 0 - 255
      Front Left: 203 [80%]
      Front Right: 203 [80%]
    $ amixer -Dmusic set Music '5%-'
    amixer: Invalid command!

    $ cat .asoundrc
    ...
    pcm.noise {
        type softvol
        slave.pcm "plug:multi_mix"
        control {
            name "Noise"
            card 3
        }
    }
    ctl.noise {
        type hw
        card 3
    }
    pcm.music {
        type softvol
        slave.pcm "plug:upmix"
        control {
            name "Music"
            card 3
        }
    }
    ctl.music {
        type hw
        card 3
    }

I'm attaching other files which define "upmix" and "multi_mix" in my
setup. As I said I think the problem re-occurs randomly when I reboot,
so I'm not sure how relevant these attachments are.

In fact I just rebooted and found the control working. But it would be
nice if I could fix this without rebooting. Also, now with the same
(previously working, just very loud) setup I get an "unknown field
channels" error when I try to play to 'music', while playing to
'noise' works fine... which is strange because "channels" only occurs
in a PCM device used by both 'music' and 'noise'... I'm not sure how
else I can try to narrow this down, without line numbers.

Thank you,

Frederick

P.S. It would also be nice if softvol controls did not have to be
associated with a physical card, but I guess that is more of a feature
request than a bug...