I'm now having a similar problem. I've been mixing up my MIDI arrangement - now I'm using the Prophet 6 MIDI out into a Kenton Thru-5 box, with the Evolver taking MIDI input from there. The Evolver isn't triggering all notes, and I've switched to the modes suggested by Chysyn, LA/LAr. Still no luck. The Evolver only triggers cleanly if I play in a staccato manner. I tried taking MIDI out from the P6 directly into the Evolver's MIDI In, but same result. I've had the Evolver for a couple years by now, never had this triggering issue before.
Anyone have further thoughts?