Re: AT sounds horrible

On Wed, Dec 15, 2004 at 08:44:16AM -0500, Jason I. Comander scratched on the wall:
> > I'm also starting to think that it's a hardware problem.  I just noticed
> > that if I power cycle the AT, it sounds fine for a few minutes and then it
> > starts sounding horrible again.  During quite parts of songs or when it's
> > not playing anything, I can also hear a slight intermittant fluttering
> > sound.  Sometimes when I change songs using the track skip button, these
> > fluttering sounds happen at exactly the same time as when I push the button.
>
> I am not sure if this fits exactly, but Could it be that the network
> activity is causing interference in the audio?

  This seems unlikely.  10Mb Ethernet uses 20MHz signaling pattern on
  the wire, so it is way way way beyond anything that is likely to cause
  issues with audio signals.  Most of the on-chip signal patters are
  going to be 20MHz, 10MHz, or 1.25MHz (data rate in bytes), all of
  which are way too high.  If it is network related, I'd guess the
  most likely problem is power management.

  Given that fact that it sounds fine when the AT is powered up my
  guess is that there is a grounding issue somewhere.  I once had
  a CD player where the initial amp chip (perhaps the DACs, or the next
  phase, I don't remember) flaked out.  It would play fine for about 5
  minutes, then get static in the audio signal.  Turning it off for an
  hour or taking a paper clip and shorting out one of the pins would
  fix it for another five minutes, until it build up enough static
  and/or capacitance to slowly start playing static again.  No solution
  but to replace it.  You might be seeing something similar.

   -j


--
                     Jay A. Kreibich | Comm. Technologies, R&D
                        [email protected] | Campus IT & Edu. Svcs.
          <http://www.uiuc.edu/~jak> | University of Illinois at U/C