I’m new here but I think you’re on the right track with the Auto Surgeon post. I bought my 2020 Ford Edge ST a couple years ago and it was great until last year when it started buzzing and rattling on mild acceleration at about 2000 rpm. My local Ford dealer was expert at finding root cause - a baffle plate inside the OEM exhaust resonator which is part of the unitary dual exhaust SYS on the ST. Dealer replaced my entire exhaust after of the cat, even though the massive ten-foot exhaust is $1200. (!) …this was done under warranty so whew what a relief. It did take a couple months to come in at the dealer due to back orders. But it solved the problem entirely!
