I cant exactly locate where the sounds coming from.. I had the cat removed & replaced with a straight pipe last summer cause it was eroded and cracked.. now its squeeks from rear while the car`s in idle, sounds fine while in drive.. must be muffler?.. time to lift the rear end and find th Sqeek!!

 

so what's the question here....you basically just told us what you're doing. but my input is the the exhaust is rubbing/hitting something. or it's not the exhaust and is a suspension component.

 

The rear exhaust squeak that eventually developed in both of my Civics was caused by a crack caused by rust in the pipe bend of the muffler.