[LAU] Question about Behringer UCA202 USB audio device

david gnome at hawaii.rr.com
Wed Jan 14 02:03:29 EST 2009


Justin Smith wrote:
> On Tue, Jan 13, 2009 at 12:53 AM, david <gnome at hawaii.rr.com> wrote:
>> Is it normal for it to have more-or-less constant low-frequency pops and
>> crackles while playing quiet passages, and occasional louder pops even
>> in louder passages? These are files that were digitally generated
>> (sample recordings of the Aeolus organ synthesizer) or ripped from CDs,
>> so they weren't analog recordings that might have such additional
>> natural sounds.
>>
> Try the "test audio and midi" menu item in puredata, with the test
> signal on the "-40" setting (or some other low level reference signal
> of your choosing). If you get the same low frequency pops and static,
> it is your sound card or driver (most likely the card). From your
> description it could be a ground loop - does it go away if the sound
> card is attached to a laptop on battery power?

Thanks for the suggestion about it being a ground loop. I tried it at 
home here with the laptop on battery power - with no change.

At my office, there was no noise problem at all.

The difference is that at home I was plugging the card into an powered 
external USB hub (ZoneNet 7-port USB2). I reshuffled USB connectors to 
give the sound card its own USB port and the noise went away.

Lovely sounding card - amazing how the Intel HDA sound chip makes the 
sound muddy, murky and distorted ...

-- 
David
gnome at hawaii.rr.com
authenticity, honesty, community



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