Looked at area around the property. Neighbor in back is much higher and it is apparent where water from their property is flowing under deck and next to the house. The downspouts are feeding into the ground and confirmed that the pipe in the round is not perforated, but cannot tell wher they lead to or discharge. Suggest confirming where downspout go and that they are flowing properly. Also suggest regrading so to keep water from flowing to house. If that does not solve water issues in ducts then suggest installing an outdoor sump pit and pump.