What is the odd feeling in your ears when loud music cuts out suddenly? (when using headphones)

When listening to music, if its fairly loud, not painfully so just emersively (if that's a word) so, if I hit pause and it cuts from qutie loud to silent I get an unpleasent feeling in my ears like increased pressure. Yet if I take them if the volume drop is even slightly more gradual like taking the headphones off this doesnt happen at all.

Can anyone explain this please? cheers!