Problem with audio apps and mixer

[Alexander Best]

thanks a bunch for all the great info.

alex

Paul B. Mahol schrieb am 2009-07-03:
> On 7/3/09, Alexander Best <alexbestms at math.uni-muenster.de> wrote:
> > wow. thanks a bunch. this new feature of having each app use it's
> > own volume
> > setting is pretty cool. however i think i'd like to preserve the
> > volume
> > setting for each application and rather not have it reset. because
> > i think
> > this feature takes the pid of the app and preserves the volume for
> > the pid.

> Negative. Same application can open and close (different) channel(s)
> multiple
> times causing volume to be changed. You can get some patches on
> freebsd forums
> for mplayer and others ...

> > mplayer and mpd however seem to fork a new instance after a song
> > change or
> > pausing etc. so so the volume get's reset while the app is still
> > running.

> Nope, there is no *forking*.

> > i might be wrong, but i think there's a typo in this description of
> > the
> > feature i'm looking for:

> >         hw.snd.vpc_autoreset (default=1, enabled)
> >             0=disable, 1=enable
> >             Notes: By default, channel volume will be reset to 0db
> >                    relative after the channel is closed which means
> >                    that any
> >                    changes will be lost and not preserved. Setting
> >                    this to
> > '1'
> >                    will preserve the volume at the cost of possible
> > confusion
> >                    for other applications trying to re-open the
> >                    same
> >                    device (see hw.snd.vpc_reset for possible
> >                    'panic' switch
> > to
> >                    fix the volumes).

> > shouldn't it be:

> >         hw.snd.vpc_autoreset (default=1, enabled)
> >             0=disable, 1=enable
> >             Notes: By default, channel volume will be reset to 0db
> >                    relative after the channel is closed which means
> >                    that any
> >                    changes will be lost and not preserved. Setting
> >                    this to
> > '0'
> >                    will preserve the volume at the cost of possible
> > confusion
> >                    for other applications trying to re-open the
> >                    same
> >                    device (see hw.snd.vpc_reset for possible
> >                    'panic' switch
> > to
> >                    fix the volumes).

> > ????

> > so after settings hw.snd.vpc_autoreset=0 each application uses it's
> > own
> > volume
> > setting AND preserves it. just what i wanted. even better because i
> > didn't
> > know this cool new feature existed. :)

> Doesn't work as expected because if you use multiple applications at
> same time
> silenced channel may and may not become extremly noise at any time -
> this is
> OSS and not FreeBSD fault and it is implemented as is in many if not
> all
> multimedia applications; so you may look again in freebsd forums and
> use
> ariff@ patch for mplayer. I don't remmember there was patch for mpd,
> but you
> can always ask politely.

> > thanks again for the hint.

> > cheers.
> > alex

> > Paul B. Mahol schrieb am 2009-07-03:
> >> On 7/3/09, Alexander Best <alexbestms at math.uni-muenster.de> wrote:
> >> > hi there,

> >> > i've never had a problem to adjust the volume with audio apps
> >> > like
> >> > mplayer
> >> > or
> >> > mpd. recently however i'm experiencing this strange behaviour.
> >> > the
> >> > app's
> >> > volume doesn't match the volume that `mixer` reports. here's an
> >> > example:

> >> CURRENT have VPC.
> >> You can completly disable such feature with this sysctl:
> >> hint.pcm.X.vpc (default=undefined, enabled)
> >>             0=disable, 1=enable
> >>             Notes: The only place to enable/disable vpc.
> >>                    Enabling/Disabling requires driver reload.

> >> here is explanation with more details:
> >> http://people.freebsd.org/~ariff/SOUND_4.TXT.html