Catalytic converter/Resonator ticking noise

https://www.youtube.com/watch?v=asVGuPFXAFk

The ticking noise is coming from either my catalytic converter or my resonator, but I can't tell which one because theyre so close together. It doesnt feel like a blockage (can't feel any backpressure, engine doesn't struggle) and there aren't any rattling noises coming from the cat when I go over bumps. 2002 Protege5 with 111000 kms and Megan Racing Cat-back exhaust. Should I be worried?

EDIT: More information: Resonator has about 3000kms on it. Catalytic converter I have no idea, but I don't think it's the factory cat because it was the least rusty piece of the exhaust system when I bought the car. The sound occurs when the car is turned off after being driven fully warm and lasts for about 5 minutes.

EDIT 2: I know it sounds a lot like normal metal cooling noises but for some reason the fact that it started so suddenly having never done it before has me concerned.

Defiantly not from the metal cooling. When everything is nice and cold shake the exhaust real hard. You'll figure out where it's coming from

I put the car up on stands and shook the cat real hard, as well as the rest of the exhaust system. Nothing rattles. I also had a friend listen while I went over a bump and he didn't hear any rattling. I get where you're coming from, I had a friend with a fried cat and it rattled around as he drove and when you shook it, but I can't find any sign of this. Everything seems to be intact. This is really puzzling me.

UPDATE: It hasn't happened in 3 days. Completely stopped on its own. This was a weird one for sure.