I'm not sure if this is the same situation, but when I played around with WASAPI in Foobar2k, the sample rate and bit depth used by WASAPI would "stick" to whatever was set in Control Panel (Control Panel, Sound, select device, Properties, Advanced), and would not switch automatically. I would get the "unsupported format" error and the file wouldn't play. I have some ripped DVD-A material, and I often do random playlists, so I wanted that capability. It was a no-go with WASAPI. I found the automatic switching of bit depth and sample rate using ASIO worked fine. YMMV. If your sound device doesn't support ASIO, sometimes ASIO4ALL can be made to work.