Jeff Evans
First of all there is no way Sonar or any other DAW can adjust the level before it hits the AD converter of a digital device....
Not completely true John. VStudio VS700R owners have control over the input Pad and level before the signal hits the A to D converter via the software control. But overall you are correct as in this case it is rather specialised. (I have checked the block diagram and unless I am wrong that seems to be the case)
If I understand correctly that has nothing to do with the record level fader in Sonar. That is a separate control that is not accessed via the Console View or the TV but rather a control panel of its own inside Sonar.
Below is from the V700 brochure.
Mic Preamp Settings
Easily access the eight digitally controlled mic preamps in the
VS-700R through the VS-700 Control Panel in SONAR and add
digital effects such as LF Cut, Compressor and Pad on each
channel. Easily save your settings as presets to use at a later time.
In other words its an add on.
Sonar can not control the recorded signal or adjust the inputs of hardware.
What Roland is doing is using the computer because they don't appear to have actual knobs on the I/O unit. Sonar though is doing nothing.