Under preferences/wave in Sound Forge I have selected :
Playback device:
DIGI9636 SPDIF out (works fine under Cubase)
Record Device:
DIGI9636 ADAT 1+2 in (also fine under Cubase)
The inputs are the AEB4/I analogue expansion board for the Hammerfal to which my keyboard is connected.
The SPDIF output hooks up to the digital coaxial input on my amp, and gives excellent sound under Cubase and Windows generally.
Best
Klytus