How to fix a rattling noise in my Audi 80's engine?

I recently noticed a rattling noise coming from my Audi 80's engine. It's not too loud, but it's definitely noticeable. What could be causing this and how can I fix it?

The rattling noise could be due to a loose or worn out belt. Check the belts in your engine and tighten or replace them if necessary. If the noise persists, it could be a sign of a more serious issue and you should take your car to a mechanic.