I consulted with the guys from surf cables about a balanced cable for the Oppo PM3 that works with the Onkyo DP X1. They offered this solution:
http://www.surfcables.com/products/speaker-cable-other-products?variant=13587387715
They also mentioned that the Onkyo and A&K pin outs are different. Unfortunately for me I ordered a balanced cable from Ultimate Ears for my customs that is supposed to work with the A&K balanced and I was assuming it was going to work with the Onkyo
.
http://pro.ultimateears.com/products/custom-accessories/cases-cables/balanced-48-black-cable
I hope I can return the cable to UE and get a new balanced cable for my customs that works with the Onkyo.
I checked the USPS tracking today and the DAP is already in my city waiting for delivery, so I won't be able to test the balanced out when I receive it. Oh well.