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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: Debugging Sound Issue with 2 Sound Cards on Windows 7: Any ideas
 out there?
Date: Fri, 24 Apr 2015 21:54:17 +0000 (UTC)
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Date: 2015-04-24T21:54:17+00:00
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Sounds more like an OS, or device driver problem.
Looking at my Claw binding, I see it calls
  pragma Import(StdCall, waveOutOpen, "waveOutOpen");
with a small integer to select the playing device.  But I don't have
a dual card Windows 7 configuration to test running two at once.