Introversion

Every time I launch DEFCON it pauses and gives me an error message. Can somebody figure this one out?:

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= BLACK BOX REPORT =
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Defcon 1.61 STEAM built Dec 1 2011
Date 1:37, 12/10/2016

ERROR : 'DirectSound ERROR
..\..\contrib\SystemIV\lib\sound\sound_library_3d_dsound.cpp line 281

Direct sound couldn't start playing a stream
Error Code : REGDB_E_CLASSNOTREG
Class not registered'

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= STACKTRACE =
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retAddress = 00416895