I've noticed the same mate. Have done some reading recently and apparently the haldex is not the quietest thing around. I notice it most while at that speed or above and just feathering throttle to maintain speed or easing off. If I accelerate, no noises. It does piss me off on long drives but I'm not overly concerned. I had an S2000 that was noisy but nothing compared to my R.
I don't think it's anything to be concerned about
Couple links...
http://www.vwgolf.net.au/showthread....haldex-whining
http://forums.vwvortex.com/showthrea...r-Haldex-whine
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