Your car sounds way healthier than mine! The noise I have was how It was when I got the car. Have you considered injector cleaner by any chance? It's a hit and miss for some people, and at an average price of £7 you cant go wrong.
Listen to my engine, that clack it has sounds horrible! Also when I drive mine through narrow built up roads you can hear the ticking like worn tappets on a high milage petrol engine. Your engine sounds fine if I'm honest, maybe just needs some cleaner through it as it doesn't take much at all to clog an injector.
https://youtu.be/Nvxn4H8RiWk