Once it starts to gurgle, the base (chamber containing water) is supposed to be rinsed slightly with water. This stops any steam from rising any longer. This is done to ensure no overheating of the coffee happens and prevents the coffee from being bitter.

PS The correct name of the faulty model is 'Metallisk'

I have real problem with the same moka pot: when the upper container is half filled the water almost stops and only steam comes from the tube. How much do you fill the lower container?

Good job 👏