Help needed: sound/audio only semi-working

Carl Johnson carlj at peak.org
Sat Oct 22 04:29:38 UTC 2011


"Ronald F. Guilmette" <rfg at tristatelogic.com> writes:

> I've been bringing up a new amd64 box with 8.2-RELEASE.  So far I've managed
> to get everything installed OK, including a boatload of freshly-built ports.
> I've even gotten flash10 working with firefox... well...
>
> Unfortunately, this is only MOSTLY working.  The video works great, but for
> audio all I get is absolute silence.
>
> The really strange thing is that after I followed all the directions here:
>
>    http://www.freebsd.org/doc/en/books/handbook/sound-setup.html
>
> This command:
>
>     cat /dev/random > /dev/dsp
>
> *does* produce quite a bit of white noise sound.  However when I perform
> the other officially recommended basic audio functionality test:
>
>     cdcontrol -f /dev/acd0 play 1
>
> with one of my favorite old audo CDs in the drive (AND with that special
> little wire running from the back of the drive to my motherboard) all that
> happens is that the CD/DVD drive apparently _does_ start to read some stuff...
> as evidenced by the blinking access light in the front of the drive... but I
> still get no sound out, and YouTube videos still aren't giving me any audio
> even though the video seems to be playing perfectly.
>
> So, um, I am grasping for ideas here on how I can debug this problem furher.
> I really have no idea what to do next to get this debugged.  I supposed that
> if nobody gives me a good suggestion, I'm gonna try swapping out that special
> little wire for another one and then try swapping the CD/DVD drive for another
> one if that still doesn't solve it.
>
> Sigh.  :-(  I just checked and yes, the CD/DVD drive _can_ mount a data CD
> alright.  No problems doing that.
>
> So how can it be that this works just fine:
>
>    cat /dev/random > /dev/dsp
>
> even while this:
>
>   cdcontrol -f /dev/acd0 play 1
>
> causes the disk to spin up and read, but otherwise produces utter silence?
>
> I'm flummoxed.
>
> Any help would be appreciated.
>
>
> Regards,
> rfg
>
>
>
> P.S.  My motherboard (w/ onboard audio) is a Gigabyte GA-M55Plus-S3G.  Here
> is what a get when I cat /dev/sndstat:
>
> FreeBSD Audio Driver (newpcm: 64bit 2009061500/amd64)
> Installed devices:
> pcm0: <HDA Realtek ALC883 PCM #0 Analog> (play/rec) default
> pcm1: <HDA Realtek ALC883 PCM #1 Analog> (play/rec)
> pcm2: <HDA Realtek ALC883 PCM #2 Digital> (play/rec)
>
> Additional info:
>
> % sysctl hw.snd.default_unit
> hw.snd.default_unit: 0

I also have a Gigabyte board with HDA audio, and it won't directly play
CD sound either.  I had already ripped all of my CDs to .ogg files, so I
hadn't needed to play the CDs directly.  I just tested ripping a small
section of a CD using cdparanoia and it does produce a .wav audio file
that can be played using sox.  I also notice on my computer that mixer
doesn't show any controls for CD audio.  Unfortunately, I don't remember
if CDs worked properly on this computer when I had Linux installed, so I
don't know if the problem is FreeBSD or the motherboard.  I did find
that I have a program called kscd (for KDE) that will play, but I
suspect that it uses digital extraction instead of playing from audio.

My system uses a Gigabyte GA-MA785GPM-US2H, and the sndstat output is:
FreeBSD Audio Driver (newpcm: 64bit 2009061500/amd64)
Installed devices:
pcm0: <HDA ATI RS690/780 HDMI PCM #0 HDMI> (play)
pcm1: <HDA Realtek ALC885 PCM #0 Analog> (play/rec) default
pcm2: <HDA Realtek ALC885 PCM #1 Analog> (play/rec)
pcm3: <HDA Realtek ALC885 PCM #2 Digital> (play/rec)

Let me know if you want further information.
-- 
Carl Johnson		carlj at peak.org



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