Windows 98 Support for WDM Audio
Microsoft does not recommend using a Microsoft Windows Driver Model (WDM) audio driver on Windows 98 "Gold" because this version of Windows does not provide the following:
Support for DirectSound hardware mixing
KMixer sample rate conversion (SRC) for capture streams
Kernel support for DirectMusic
However, Windows 98 does support the following WDM capabilities:
WDM version 1.0
Audio port drivers: Topology, WaveCyclic (without hardware acceleration), and MIDI
MIDI miniport drivers built into Portcls.sys: FMSynth and UART
USB audio: Basic support for wave rendering and capture
For a description of how your driver can perform a runtime check to determine whether it is running in Windows 98, see Installation Issues for an Audio Driver in Windows 98.