On my system the WDM works very well for some sample rates but not with outhers.
I have audio device firmware and driver debug experience, and offer to lend you guys a hand. With MS's continuing lack of USB Audio Class 2 drivers, the WDM is a very important thing for audio consumers.
My: system: Player is JRMC17, DAC is
www.henryaudio.com in USB Audio Class 2 ASIO mode, OS is Win7-64. Source: wav files converted to the 6 classical sample rates (44.1 up through 192) by JRMC17 or 18.
The DAC and source material work very well with MC 17 & 20 in normal operation. With 20.0.41's WDM and MC17 as the player it's OK with 44.1, 88.2 and 176.4ksps, but I get silence with 48, 96 and 192.
Setting the protocol to WASAPI event style in the player, the DAC (operating through WDM and ASIO driver) is correctly using those three sample rates (yeah! no resampling). With WASAPI (not event style) I get an unreliable playback. With Direct Sound I also get audio on 44.1, 88.2 and 176.4ksps material, but now everything is resampled to 44.1. With DS I also get silence on 48, 96 and 192.
I kind of expected DS to resample all 6 rates to the default sample rate set by the OS, and both kinds of WASAPI to forwared the source material 1:1 without sample rate conversion.
Best,
Børge