Andrey,
If I set its speakers interface as a default device in Vista Then I see XX engine 3 in the Vista Mixer, The Vista master volume affects the volume of the music.
Ok, so far I never saw (or heard of) the situation that loudspeakers connected to a soundcard could incur for "Exclusive Mode" (whatever that exactly is in this stage of "investigation").
Can you confirm dat this worked the same in 0.9t ?
Also, I assume you don't get any messages at the start of Playback ?
How can record what is coming out to compare to the source?
This is a quite undoable task, but which I solved for myself about a year ago by means of two Fireface devices. This is inherent to how Vista works and determines when to apply the proper Exclusive Mode. This is similar to connecting a DTS receiver and that just "proving" bit perfectness, which for Vista says NOTHING.
Currently I don't have the answer anymore, and it took me several days to set it up and prove it back then.
Lastly for now, do note that the situation exists that no volume amplitude information (the green bar) shows, BUT you can still switch off the volume with the bottom button (a red circle appears then). I never tested the true merits of that situation, but it sure is fishy. By me proven bit perfect situations can never switch off the volume.
Anyway if you can influence the volume with the master volume slider, I'll bet it's not bit perfect.
So far for now. Sorry ...
Peter