Have searched for roaring noise for my 02 XK8 to no avail. Noise has occured when driving 55 to 70 mph. Sounds like something hitting the fan or maybe like dragging a branch. Jag dealer found nothing did a 60K service with ex Jag mechanic. He found nothing.
Other day I noted I could make noise come on and off by accelerating to 55 and dropping down to 40 mph. It was a particularly windy day! That lead me to examine for loose parts under front of car. FOUND IT!!! The plastic guard on the underside of the front bumper had come loose on one side. Its that part of the car that always hits curb when you park head in. The darn thing was flapping in the high wind!! But when parked you would not know it was cracked on one side.
Add that one to the list of weird noises!

 

Hi Paul did you get sorted?
Stu