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!
My Krell amp doesn't have CAST inputs but I am sure you can only use one. The same goes for RCA vs. XLR, it's one or the other. A krell pre amp out is different and you can use both outputs with no problem, you can download your manual from Krell to be absolutely sure.
You have to have CAST outputs to use CAST inputs.
Thanks, guys!
so the usual adapter cannot work with CAST, hugh?

CAST cary signal as current while RCA and XLR cary signal as voltage. Use an adopter and prepare for a funeral of FPB!
>>CAST cary signal as current while RCA and XLR cary signal as voltage<<

Could you elaborate on that a bit more please.

Thanks in advance.
Just read the page 3 of Krell FPB manual, available online at Krell website.

However, page 1, Krell Current Audio Signal Transmission
(CAST): “A proprietary Krell circuit technology for connecting analog components, in which the audio waveform is transmitted between components in the current rather than voltage domain.”
CAST: high impedance output into low impedance input

Balanced/single ended: low impedance output into high impedance input
thanks again for your comments!

i decided to simply use the balanced inputs as getting krells with cast in this side of the pond is very difficult - people are simply keeping theirs ;-)