hints for troubleshooting poor sound quality.

[Lowell Gilbert]

George Hartzell <hartzell at kestrel.alerce.com> writes:

> Lowell Gilbert writes:
>  > George Hartzell <hartzell at kestrel.alerce.com> writes:
>   > > I've set up an ASUS small form factor machine based around an P4S8L
>  > > motherboard.  It's running 6.0BETA4 and Gnome2.12 from the tinderbox
>  > > packages.
>  > > 
>  > > I'm kldload'ing snd_ich and (after getting a helpful pointer to the
>  > > gnome FAQ) all of the sounds stuff is working.
>  > > 
>  > > Here's my problem:
>  > > 
>  > >   The machine has two mini-jacks, one in the front and one in the
>  > >   back.  If I plug a set of headphones into the front jack I hear all
>  > >   kinds of clicks and whirs and buzzing.  They seem to correlate with
>  > >   drive activity, cd activity, and maybe even the cpu fan.  The
>  > >   connector on the back seems quieter, but I still hear a bit of
>  > >   noise.
>  > > 
>  > >   I hear less noise on a set of sony powerer-subwoofer-and-tweeter
>  > >   speakers, but it's still noticable.
>  > > 
>  > > I haven't been able to try another sound device, the only spare card
>  > > that I have doesn't fit into the space provided (riser card).
>  > > 
>  > > I'd appreciate anythoughts about dealing with the noise.  Is this
>  > > something electrical w/ the motherboard?  Something about my Freebsd
>  > > setup?
>  > 
>  > Well, yes, it *is* electrical interference on the motherboard.  You
>  > may be able to reduce its impact, though.  Reducing the amplifier gain
>  > (ogain in the mixer(8) output) may help, for example.  Also, does
>  > playing digital audio see this effect, or only playing CDs?  If the
>  > latter, you can switch to digital extraction for playing CDs (most
>  > software doesn't support it, but some does) and avoid the
>  > interference.
> 
> Thanks for the feedback.  The noise seems to be there when nothing's
> happening, when I'm playing an mp3 from disk (that's what digital
> audio, right?), and when I'm directly playing a CD.

There may not be anything software can do, then.  Although you still
might want to try the earlier suggestion about reducing the amplifier
gain.

> Would a pci based sound card be immune from this?

One would hope.  But not necessarily.

>                                                    Any recommendations
> for one that's not as tall as a sound-blaster LIVE card (space
> constraints in the case...).

I have no idea; I haven't bought any for years...