I am confused about the state of audio drivers in Vista. I've been reading in this list and in newsgroups about how the audio subsystem has been rearchitected in Vista, moving most audio processing into user-mode. And yet, the documents on APOs describe connecting to kernel streaming drivers, just as in XP. Will KS and AVStream audio drivers continue to work in Vista just as they have in the past? Let's say one has an echo cancellation driver, that needs to tap into both input and output. In XP, that can be done as a WDM filter driver. The document on sAPO says specifically that this is not possible with an LFX or GFX filter (if I read it correctly). How would one implement such a thing in Vista? Can it simply remain as a kernel filter driver? -- Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc.