Car back with dealer as too many erroneous issues - e.g. driving up M25 towards A127 junction - "turn right...."; after re-route "take 4th exit at roundabout in 400 yards" - next roundabout is 1.5 miles away; take 4th exit in 1 mile just as you approach 300 metre markers or 1/3 mile sign; constantly late in instruction to take left off roundabouts. One destination street it says is restricted access and largest house number 28 but details entered are for street with double decker bus route and numbers over 100 which have been there for 50 years. Dealer tried another 2015 Q3 and same problem with latter. I've tried 2 A3s and they're fine. Currently with factory in Germany.

Anyone else noticed anything strange or slow responses from system?

Not heard of this before but very interesting. Sounds almost like the GPS calibration is slightly off?