I'm almost certain that it is inside the muffler, so it will be replaced.
But as you said, it's not terrible so it can wait until after the holidays now.

 

I have just had a reply from the company that sold the exhaust to me, they said;
"So what is happening is that the soundproof mesh inside of the end tip is getting lose. A good solution is to cut open the muffler and reweld the mesh into place."
which is what I suspected the issue to be. However, I did not expect that to be a solution, I have a friend who can weld so it may be worth talking to him about, before going and forking out a good few hundred on a new exhaust.

They also said they can offer a partial refund for me, even though I am out of warranty (only by a couple months though).

 

Good luck! Tell us how this "fix" worked out.

Thanks!

 

Wait, is this a Ballade exhaust?

 

It would be interesting to see an OEM muffler cut apart.

 

Mine isn't, it was made by a company based in The Netherlands. they offered to do the fix for me. but it would involve either taking the car to them, or shipping the exhaust, neither of which is practical.

 

There's a photo in this thread about the UK mod back in 2017

https://www.s2ki.com/forums/s2000-mo.../#post24187436

 

Seeing a close-up of the weld work on the OEM Sankei would be nice. Only doing minor tack welding on an object that undergoes heating and cooling cycles, plus vibrations, seems sketchy.

 

Which is apparently the exact failure mode of the Ballade exhaust

 

Nothing better than cheap shitty welds.