HELP: Krell CAST and Balanced Inputs

I have an FPB 200c and had recently went preampless, using a delius DAC to drive the amp directly. But this displaced my analog front and that drives me nuts.

I asked an audiophile firned to make for me a passive attenuator and he made it with a balanced out so as to mate with my amp. However, i also want to use the digital and i don't want removing the ICs.

Is it possible to use the XLR and the CAST inputs at the same time? What i mean is to use the Delius into the XLR and the Passive Attenuator into the CAST (using an XLR-CAST interconnect).

Has anything similar been experienced or done by anyone here?

Thanks friends!
egay