[ALSA - driver 0001151]: Audigy sampling rate seems off

[bugtrack@alsa-project.org]

The following issue requires your FEEDBACK.
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<https://bugtrack.alsa-project.org/alsa-bug/view.php?id=1151> 
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Reported By:                felix
Assigned To:                jcdutton
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Project:                    ALSA - driver
Issue ID:                   1151
Category:                   PCI - emu10k1
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Distribution:               Suse 9.1
Kernel Version:             2.6.5-7.147-default
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Date Submitted:             06-02-2005 23:07 CEST
Last Modified:              07-25-2006 00:46 CEST
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Summary:                    Audigy sampling rate seems off
Description: 
I'm doing an experiment that involves generating a tone, sending it out
the
sound card and into a (passive) circuit, and recording from the circuit
back
into line in at the same time.

When I play a sample: mono, 8kHz sample rate, containing a synthetic 1kHz
sin signal, the recording I get is of a signal 1000.12Hz. If I send 100Hz,
I get back 100.012Hz. I use 'snd' to do a 256K-point FFT across a 10
second sample just to be sure. I've also verified this using FFTW and
correlation-based programs of my own.

I've also verified that the reference 1kHz and 100Hz signals are exact.

As a sanity check, I tried the same experiment on the built-in sound card
on that same PC. The signals come back correct.

Note the seeming coincidence that the frequency of the signal coming back
is 1/8000 higher than the signal output.

I've never seen anything like it. Not that I've been looking before...
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----------------------------------------------------------------------
 felix - 06-04-05 03:58 
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Two more exciting data, to see whether it is possible to isolate the
problem to playback or recording:

1. synthesize and aplay a 1kHz tone at 8kHz sampling rate,
   simultaneously record at 12kHz sampling rate
   => Recorded tone is shifted up by ~ 1/8k

2. synthesize and aplay a 1kHz tone at 12kHz sampling rate,
   simultaneously record at 8kHz sampling rate
   => recorded tone is EXACTLY 1000Hz

----------------------------------------------------------------------
 jcdutton - 07-25-06 00:46 
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Is this still a problem with the latest alsa driver?

Issue History
Date Modified  Username       Field                    Change              
======================================================================
06-02-05 23:07 felix          New Issue                                    
06-02-05 23:07 felix          Distribution              => Suse 9.1        
06-02-05 23:07 felix          Kernel Version            => 2.6.5-7.147-default
06-03-05 00:29 sst4           Note Added: 0004879                          
06-03-05 10:59 perex          Note Added: 0004883                          
06-03-05 17:44 felix          Note Added: 0004884                          
06-03-05 17:45 felix          Note Edited: 0004884                         
06-04-05 03:42 felix          Note Added: 0004885                          
06-04-05 03:58 felix          Note Added: 0004886                          
07-18-06 14:45 jcdutton       Status                   new => assigned     
07-18-06 14:45 jcdutton       Assigned To               => jcdutton        
07-25-06 00:46 jcdutton       Note Added: 0011217                          
07-25-06 00:46 jcdutton       Status                   assigned => feedback
======================================================================



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