Why do my ears always pop, especially when I am active?

My ears do the same, so i asked a doctor. he asys that you should clean your ears because when u are active as in talking or at a loud event, you can start talking and your eardrums will push inwards. that allows more of that congestion in ur ears to come out.... URKing your ear (urk is just a word i maded up like this "urks" me)