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Re: audiorecord producing only white noise



Aaron J. Grier wrote:
> With nothing running, I'm able to play the
> > tape through the sound card to the speakers.  So the hardware's OK, or
> > at least hooked up correctly.  
> 
> as a wild stab in the dark, if your tape deck is
> playing through your sound card, you could try setting
> inputs.dac.mute=on and record.source=mixerout, then recording.

Hi Aaron, thanks.  No joy.  :-(

After trying many permutations, I'm still where I started, basically.  I
can:

1.  Play tapes through the soundcard.  
2.  Play WAV files. 
3.  Create files that audioplay(1) recognizes as cd-quality WAV files, but
which it plays as noise.  My Mac plays these same files identically.  

I get the exact same noise no matter whether record.source is mic, cd,
line, or  mixerout, and no matter which devices are muted during
recording.  

The noise isn't white, really.  It's pulsating and harsh (quite different
from your octothorp project).  ;-)

Setting inputs.dac.mute=on has the effect of suppressing the noise during
recording.  Otherwise, during recording, I hear both the noise and the
tape output on the speakers.  

> the mixer controls are working.  

We know this because I can affect the settings with mixerctl(1)? 

> for ac97 parts, the record controls
> takes a signal path separate from the mixer.  

I'm not sure what you meant, sorry?  

> your problem seems limited to ADC operation.  

Maybe it's not meant to work?  The audio(4) man page (2.0 and -current)
says, 

        "If the device is used in mmap(2) it is currently always 
        mapped for writing (playing) due to VM system weirdness."

And auvia is at least mmap capable: 

$ audioctl -a | grep mmap
properties=full_duplex,mmap,independent

Anyway, we seem to have narrowed it down to software or hardware.  

Regards, 

--jkl


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