Using an HDMI to DVI adapter will let you pass video through the 990, but it won't deliver audio. For that, you need either the multichannel analog connection or a digital audio cable (coaxial or optical). If you switch back to using the multichannel analog for your SACD player, you will lose the lossless audio formats (TrueHD, DTS-HD Master Audio, and good ol' multichannel PCM). That will result in a sacrifice in sound quality.