Are you using the same battery on both?
Keep the fix low and increase the Dwell to 30. That is what the AGD software is.
Put fix at 46. Increase dwell gradually to see if it will start firing reliably. Let's see if any dwell will work, and go from there.
I main a barbarian, working on witch doctor and wizard setup but can't find one I like, my paragon is roughly 550ish