Audio playing fast on 6.x (Looking for Ariff Abdullah)

[Nikolas Britton]

On 1/6/06, Ariff Abdullah <ariff at freebsd.org> wrote:
> On Fri, 6 Jan 2006 08:24:02 -0600
> Nikolas Britton <nikolas.britton at gmail.com> wrote:
> >
> > Thanks for your quick reply. I tried the above and playback is still
> > fast, changing it to any number doesn't seem to do anything. I also
> > cannot set it with loader.conf. I have to do it manually after the
> > system is loaded, Is this normal? Here is what I have in
> > loader.conf:
> >
> > sound_load="YES"
> > snd_ich_load="YES"
> > hw.snd.pcm0.ac97rate=48000
> > hw.snd.ac97rate=48000
> > hint.pcm.0.ac97rate="48000"
> > hw.snd.maxautovchans=4
>
> Put hw.* into /etc/sysctl.conf.
>
> Ok, since you said none of it works, how about this:
>
> # kldunload snd_ich
> # kenv hint.pcm.0.vchanrate=48000
> # kldload snd_ich
> # sysctl hw.snd.maxautovchans=4
>
> Note: 1) anything that begin with hw.* should go into /etc/sysctl.conf
>       2) anything that begin with hint.* should go into
>          /boot/device.hints
>
>

Problem solved, solution:

/etc/sysctl.conf:
hw.snd.pcm0.ac97rate=56250

Turns out ac97rate was the problem but it needed to be bumped up, not
down. I found two main threads and a PR with the same problem:

May 2002, fast playback with Intel 82801BA (ICH2):
http://groups.google.com/group/sol.lists.freebsd.multimedia/browse_thread/thread/799ffc490546679e/

Feb 2003, Hyperactive ICH2 sound (with workaround):
http://groups.google.com/group/mailing.freebsd.current/browse_thread/thread/f1017788cd486d50/

kern/31521 : [sound] pcm0 plays too fast on Intel 82801BA (ICH2):
http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/31521