Anyone else have this weird, intermittent rattle?!

Heya
Odd one this, but on long journeys my 2004 TD4 Freelander has a rattle like those things we used to stick in a bike spokes that came free with in a cereal packet! It speeds up and slows down with the car, makes the noise when coasting and out of gear, and gets louder the longer the journey. Weird thing is, it sort of ‘repairs’ itself (magic I know) and goes away for a while before another long journey comes along. I’ve taken it to two mechanics as it drives me nuts and they both tell me they don’t know what it is. To me, it sounds like it is just the other side of the bulkhead on the passenger side. Any help would be greatly appreciated. Thanks!

Check crankshaft pulley, the rubber delaminates

Brake dust shield ?

I've had VCU bearings tick before now. And very occasionally, a wheel can creak if all the nuts aren't at the same torque, so check the wheel nuts.

One mechanic on mine said there was nothing when had such an annoying noise. Got out nothing. Went to another one. He took it home to have a longer ride as he couldn't hear anything in the short test. He took it and said he could hear something but then came into a traffic jam. Next morning the way back he said it was gone again. He told me they'd taken apart a drive shaft once and sometimes there was noise and sometimes not, depending on when the parts moved from their original position and back. Maybe you could also have a look into that. Got it changed and one noise less.