Korg EX-8000 digital delay not working

Unit works fine except the delay does absolutely nothing. I see that the delay is on its own board but not sure how to proceed. The schematic I downloaded is a little hard to read due to either scan or print quality. There are three connectors going into/out of the delay board, one I’m assuming is inputs/outputs, the other is probably data controls, the other I have no idea.

The one thing I’ve noticed is that if I set the parameter to control the level of the delay and I move the value knob, a little clicking sound comes out as the values change. It is the only parameter that produces this click - all others are silent.