Comment 7 for bug 208920

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Jamie Lokier (jamie-shareable) wrote : Re: [Bug 208920] Re: PCM volume too high after upgrade to Hardy

Brian Murray wrote:
> I spoke to Daniel Chen on irc about this bug and he indicated that
> capturing the file '/var/lib/alsa/asound.state' before and after
> upgrading would be helpful. He also said the following:
>
> 15:19 < crimsun> bdmurray: I briefly spoke with someone in +1 about
> writing a script to parse the state file (/var/lib/alsa/asound.state)
> parameters on dist-upgrade (well, really between different ALSA-driver
> versions). This is likely the culprit you guys are seeing -
> particularly if it's reproducible simply on dist-upgrade (from foo to
> hardy) in the cli with aplay or paplay

I'm thinking that either:

    1. ALSA should be unable to set an "impossible" volume level,
       regardless of contents of /var/lib/alsa/asound.state. So even
       when the parser script is fixed, there's still a bug, where
       some component can be given a bogus parameter which it doesn't
       bounds check.

    2. Or it's an ALSA internal feature that impossibly high volume
       levels can be set. In that case, it's occasionally useful
       (when you're playing very quiet recordings, for example), and
       should be exposed through the normal volume controls, perhaps
       with a switch to disable the normal limit, and with finer
       control than normal/too-much of course :-)

-- Jamie