C'è una beta avanzata per WASAPI v.3... Handle with care:
"Thanks for the report, I was kind of expecting this issue to show up.
Event mode in fact provides worse protection against CPU usage spikes than push mode (as seen in earlier versions of this plug-in) because we queue less data with the driver at a time and must wake up and send more data at regular intervals. However, event mode seems necessary to peacefully cooperate with certain devices, USB ones in particular.
Manually overriding priorities of fb2k & WASAPI host exe processes in task manager might help you. I'll look into other means to improve resistance to system resource usage spikes. "
WASAPI plug-in version 3.0 beta - Hydrogenaudio Forums