Reply to Mapping a monitor to each sample

hi

i'm usually quite confident with mappings but i've been beaten this time.

i am running traktor pro 2 with an apc40 mapped to decks A&B. everything is fine here.

i also have a behringer bcr2000 that i want to map to sample decks C&D.

I want to have a monitor on each of the samples (8 in total). any ideas? I can't see where i select deck 3 slot 1 etc...

do i need to add a modifier or something?