First I would check pump output pressure at load sense port on pump in question. Determine if the hyd functions are slow or weak or both. Swing pressure for 330B would be anywhere from 3200-3900 psi. Travel from 4000-5000 psi. A simple easy test you can do to narrow your search is to swap circuit relief valves to see if problem follows relief valve. If load sense reads low possible problem with P.C.O relief valve. If pump strokes, builds high pressure, but is slow doing so possible margin pressure adjustment required. L.S signal acts on pump output pressure plus margins pressure if margin pressure is not right may not allow pump to reach full stroke therefore not displacing the required oil in a given time frame. Saying all this is fine, I try to check all the simple things first!!!!. The reason the pump was replaced was??? Could there be debris in control valve?