recently picked up a cd7000 HU...and i seem to have a bit of trouble setting it up.

is it supposed to be set on the "3way" or "4sp+sw" setting? my subs seem to barely hit on 4sp+sw..

 

If you have front + rear + sub[s], set it on 4sp+sw. The other setting is for a tweeter, midrange, and sub[s] - otherwise known as "active" crossover. Active is where you have a dedicated pair of amplifier channels for each speaker (tweeter, midrange, sub[s]).

Are you 100% sure you've got the RCAs connected to the subwoofer (non-fading) output? Is the crossover set correctly on your amplifier? What frequency are both the CD7000 and amplifier set to? If possible, you should bypass the amplifier's internal crossover when you're using the source unit's. Where is the gain set on the amplifer[s]?