what should that be set for?

I figured out the distortion, that was simple overload, i'd accidentally moved the volume sliders to +12 instead of 0. Changing that solved it. I did adjust center speaker volume though. Using the Speaker test option in kX all work but the center.

So what SHOULD i get then to get all this to work properly? The DTT3500 control unit is supposed to be able to decode digital, so shouldn't that be sufficient? Or should i supply it with an analogue signal from the sb?