Pre-cueing Using BCD-3000?

Hi, first I’d like to say thank you for an innovative, relatively simple, and affordable mixing app! I’m brand new to this so if the description of my problem doesn’t make any sense, please let me know.

I have an old Behringer BCD-3000 that has a headphone jack that I can’t figure out how to set up for pre cue. I tried setting up an aggregate device in Midi Setup but couldn’t figure it out. I know the headphone jack works because if I switch BCD to my main output and my laptop headphone jack as my precue it will work, but only through one speaker. Which is fine for now, I think. I have soundflower but no idea how to use it. I know about the splitter, but prefer stereo sound and would like to avoid that route if possible.

In djay preferences it won’t save BCD in the pre cueing option. It lets me select it, but when I hit apply it kicks it out. I tried using both channels 1-2 and 3-4. I was able to map the phones mix knob but it doesn’t seem responsive.

Any Ideas?

Actually, I think I’ve got it figured out!
I had to download something called “MidiPipe,” and set up my controller under Output > Midi Out. Then set up an aggregate device under audio midi setup, selecting only my controller and setting the pre cueing output to channels 3 and 4.
Hope this helps someone else! And I’m still open to hearing any other solutions, if any.