You probably should try it the serial loop and have the wet dry mix on the pedal. This will keep phasing problems away. I don't have dd20 or a V but I use the empress delay in the switchable serial loop of my Hagen.
That is exactly the issue that I had trying to run it in the parallel loop. I have it in the serial and it is working just fine. I just wanted to know if anyone had success running it the other way. From what I understand, the serial loop on the 4 is not programmable.