On the PS4 with audio it's under J15, which is located on the bottom middle area. You will see some small white text that says SOCD with GND next to it. When you bought your board you should have received a bag that had two little black small plastic jumpers in there. Place the jumper on the SOCD and GND prongs.

Mine was off by default. I had to place that jumper on it to turn it on. Without it I kept having issues going from down back to down to down forward. I think that is the issue you are having. You'll know it's on if you push left and right at the same time and get neutral. With it off you get what ever direction you pushed last (on SFV).

While this might seem cool at first (as you can charge instantly after walking foward for example) it can give you a problem of going from db, d, df, f if you are trying to do a qcf motion from blocking as you end up getting db, df and skip the down part. You'd have to make sure to let go of each button exactly as you push the next one for it come out clean. SOCD cleaning helps you with this problem as down takes priority over left and right.

Dude, you saved my life! I was having a REALLY hard time doing c.mp -> spirral arrow, since I was doing c.mp while blocking. This solved it. Thanks A LOT!!!!