The answer to 'P-trap making noise' is that a noisy or gurgling P-trap is typically caused by a blocked or partially clogged drain. This can happen when debris, hair, or other materials build up in the trap, preventing proper water flow and causing air bubbles to get trapped, which create the gurgling sound.
To fix a noisy P-trap, you'll first want to try plunging the drain to clear any blockages. If that doesn't work, you may need to disassemble the trap and clean it out. This is usually a DIY-friendly task, but if you're not comfortable working on plumbing, it's best to call a professional plumber to diagnose and resolve the issue.