FWIW, I indeed swapped out the 59/C for the Dimarzio 36th (DP223) in my SD22 and it solved all my odd frequency anomalies. I have the 36th paired with two SSL2 and the guitar is very balanced now.
As great as the 59/C is, it is not a good match in this maple bodied guitar. YMMV of course
Both pots are 500K