First, SACD's are more than just a "high resolution CD" - they are a completely different format using a higher capacity disc (think "DVD"). The SACD standard does not allow audio output at all of the SACD layer(s) via coaxial or optical. It is part of the licensing agreement, and the only player to ever circumvent it was the original PS3 (which had SACD support and could output SACD's in stereo over optical). The BDP-93 cannot output any audio from SACD's via optical or coaxial. You must use either HDMI (not an option with the Model 950) or analog audio outputs. Since you've got the BDP-93 connected to the Model 950's 6CH input already, use that for SACD's just like you do for Blu-ray.

Second, DVD-Audio is a similar "high resolution CD" - it was SACD's competitor in the high resolution audio disc format war that both formats largely lost when the iPod combined with bad marketing and stupid restrictions on digital output to relegate SACD to a niche market and DVD-Audio to even greater obscurity. DVD-Audio can be output via optical and coaxial, but it's limited to downmixed stereo. Again, I'd recommend using the BDP-93's analog output.