I am just guessing, but if the female insert in the board is spinning, then the connection to the fiberglass is already broken, so the board is not water tight anymore. This would require either pulling the insert and glassing in a replacement, or pulling it and glassing over the hole. If you do pull the insert out and think that you are going to be doing future windsurfing, I would recommend replacing the insert with a more standard mast track that will solve any future spinning problems. The Fanatic inserts are not a strong idea because of the potential spinning problem. If you do not want to go with a full mast track, which you really don't need, check out what Sunova puts in their SUP boards. It is a windsurfing mast track cut down to just a couple of inches in order to save weight and a large cut into the deck of the board, but it still has a solid system that is plenty strong and versatile for windsupping.