When driving around today, I've noticed that the vibration happens just as you put the power on (turning hard right). Once the revs as increased a bit, it goes away.
Am starting to think this could only be a driveshaft bearing of some kind.
I have the exact same issue at the moment, always rumbles when turning hard right with a bit of power, doesn't do it very often turning left. I think its some sort of bearing problem, hopefully I'll have some time this weekend to have a proper look.
Good to know we're not the only ones! Let us know how you get on. Ours hasn't done it for the last couple of days. Its quite random so its hard to locate it.
Fitted new VCU support bearings today (OEM ones). Has made a massive difference. Rumble / vibration has completely gone, less road noise too. All sorted.
