My Ps4 Pro is cool but still very loud?

When I play a game my Ps4 Pro gets very loud. So loud that you just can't enjoy it without headphones because you can't hear anything from the game. My Ps4 itself always feels pretty cold and is also clean inside. What can be the reason?

New thermal paste

Otherwise there's nothing you can do if it is clean and not defective

Are you sure it is clean? Did you check that and clean all the dust? Unfortunately, all consoles are often very noisy because they don't have enough space to cool down. The cooling is also smaller and definitely not as effective as the desktop.