Range Vent Hood ducting brings windy noise!!
Do both the hood vent and the roof vent have dampers installed? They should. While a stiff wind might lift the roof damper, the hood damper generally stays closed. If both dampers are indeed in place, I would call the hood manufacturer and ask for recommendations.
If the ducting runs through an attic you might install an inverted "Y" piece with it's own damper gasketed on the attic side. When the wind draws across the roof vent the "Y" damper would pull open and draw attic air instead of hood air. When the fan was operating the damper would be pressed closed by the air pressure of the fan.