i think you're out of luck...the point of laptop
architecture is to squish
everything together....with a monitor and usb (which is fairly high voltage)
so close to an integrated audio card, you cannot avoid magnetic influence as
shielding at this level is practically impossible....you're best bet (and
not a very good solution) is to get a breakout box so the actual dac is
physically outside the laptop. If you come up with better solution please
let me know,its a problem that frequently drives me nuts
From: Ben Saylor <bsaylor(a)Macalester.edu>
Reply-To: linux-audio-user(a)music.columbia.edu
To: linux-audio-user(a)music.columbia.edu
Subject: [linux-audio-user] hum from laptop soundcard
Date: Fri, 18 Apr 2003 13:57:06 +0200
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FILETIME=[AE502DA0:01C305DC]
Hi,
I have a new Dell laptop with a headphone jack as the only external
audio output. With headphones, the sound quality is good and there is
little noise to be heard. However, if I plug in my monitors, the
output crackles and hums, regardless of the mixer levels. There is
217 hz constant hum, a 125 hz hum when moving windows, and a 689 hz
whine when I run Pd. The output crackles when I move the mouse
(external USB). I just noticed that it goes away when I unplug the AC
adaptor. I think I remember a similar problem coming up on this list
before, but I had no luck searching the archives. How can I solve
this?
Thanks,
Ben
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