When you try to play a non-PCM (Pulse Code Modulation) WAV audio file on a Windows 2000 computer with WDM (Windows Driver Model) audio drivers installed, no sound is produced.

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This behavior occurs because the Wdmaud.drv (WDM Audio Driver Mapper) file interfaces with Kmixer.sys (Kernel Mode Audio Mixer), which supports only the PCM audio format.

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To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

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To work around this behavior, install non-WDM drivers for your audio device.

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Microsoft has confirmed that this is a problem in Microsoft Windows 2000.

This problem was first corrected in Windows 2000 Service Pack 2.

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Devices such as software-based DVD players require the use of non-PCM audio formats to play content like AC3 (Dolby Digital 5.1) audio.

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