WinME:
Go to START MENU, SETTINGS, CONTROL PANEL, SOUNDS & MULTIMEDIA.
At the bottom under Scheme, select No Sounds and answer NO to "Save current scheme?"
Select DEVICES tab, and expand the AUDIO DEVICES item.
Double-click the pro audio card, and checkmark the box "DO NOT MAP THROUGH THIS DEVICE" and hit OK.
This will disallow Windows from using your audio card while you're in a recording program. If you have a Soundblaster-compatable card still installed, Windows will now use it for Windows sounds.

Win98:
Go to START MENU, SETTINGS, CONTROL PANEL, MULTIMEDIA
Select DEVICES tab, and expand the AUDIO DEVICES item.
Double-click the pro audio card, and checkmark the box "DO NOT MAP THROUGH THIS DEVICE" and hit OK.
This will disallow Windows from using your audio card while you're in a recording program. If you have a Soundblaster-compatable card still installed, Windows will now use it for Windows sounds.
Go back to the CONTROL PANEL, SOUNDS.
At the bottom under Scheme, select No Sounds and answer NO to "Save current scheme?"

If you are still having problems with your Digi001, you may want to go back to this menu and also select "Do not use audio features on this device" which will disallow any Windows program (except Pro Tools) from using the device.