Hello I have question have any of you had this issue where the muffler fell off at the point of the flange. What did you do? Is this a quick fix or the whole muffler should be replaced. I have done some research and this could be corrected with a straight pipe, what are your thoughts? This also seems to be a reoccurring issue with Honda mufflers in general.

 

I've got a 2014 Si Sedan, and have been daily driving it in Michigan. I noticed a lot of rust and corrosion on my exhaust at the flange you were talking about.
I put a catback system on mine, but I busted an air driven ratchet breaking the bolts loose where the muffler flanged to the pipe to the cat... and threw the busted tool and towel in and just ended up paying someone to remove the pipe from the flange behind the cat. Not sure where you are in Canada, but I bet your winters are the same or worse than Michigan.

For your question on ease of fixing, depends on what the flange looks like after you get the fasteners out of it. if it's real mangled it'll be a good excuse to get a catback system. If you think the Flange will still work on both sides, new fasteners should do it. Or if the muffler flange is shot, but the pipe still on the car is good, you should be able to get a muffler only to replace it. Either OE or Aftermarket, there is a handful of options for the 9th gen.