My wife and I just purchased a home with an IG gunite pool and this is my first post. The pool has a vacuum port located in the center of the long edge for the Hayward Navigator to plug into. One thing that I have noticed is that when I unplug the vacuum hose from the port and the lid on the port closes the pump gets much louder. I have also noticed that there is much better flow from waterfall when the Navigator is hooked up. I have already verified that the skimmer is working and pulling in water. My question is am I doing something wrong or is this normal? Also is there something that I can plug into the port when the hose is not in place to maintain the higher flow?