Hey guys, potential new XJR owner here. There's a 2006 I'm looking at to purchase, but I want to get some opinions on an issue it's having first. I've not seen the car in person, it's in Georgia and I'm in central Florida, I intend to have it shipped. Its main issue that I'm aware of is a sort of rattling or "fluttering" sound at around 1500rpm. The dealer sent me a video (linked below), but their techs aren't sure what it is. It also had a misfire at one point but that's disappeared after they did further inspections on it. I do have some mechanical background but I'm not familiar with Jaguar at all, I'm hoping someone here might have some idea of what this could be. Thanks!

https://streamable.com/klsm88