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Date: Tue, 22 Nov 2005 16:17:42 -0700
From: "Jonathan C. Forster" <jforster@psy1.psych.arizona.edu>
Subject: [DMDX] Re: voice key failures


There's a whole slew of RecordVocal and DigitalVox issues that produce 
exactly the symptoms you describe and that have described by me in great 
lengths in the past, the finer details of which I never remember.  Check 
the help on RecordVocal and the archives and you should find all the 
information you need, it's all I'd be doing in any event.

At 05:42 PM 11/22/2005 -0500, you wrote:
>Jonathan, in a current picture naming experiment, we've noticed that the 
>voice key is being triggered erroneously on about 5% of the trials. I've 
>attached a wav file for you to look at, but essentially the subject makes 
>a response but the voice key doesn't trigger until 800-2000 ms later.

   The voice key is probably triggering correctly however the data that is 
being written out is likely to be out of phase however.

>   If it didn't trigger at all, I wouldn't be too concerned.  But the fact 
> that it's being triggered by no apparent acoustic signal is 
> disconcerting.  Any ideas?  We noticed this happening a few days ago on 
> one of our machines, and I first thought it may have something to do with 
> that machine; but today the same thing happened on a separate machine, so 
> I'm inclined to think it's a DMDX thing and not a machine specific problem.

   It's an audio driver and operating system issue.

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