Can anyone give a clue on a noise apparently coming from the front of the car at 65-70mph in 5th gear. It is quiet at lower and higher speeds. The car is a 2012 greenline 1.6d.

Droning noises are often wheel bearing or tyre issues. That is where I would start, are the tyres okay, any odd wear patterns / feathering on the inner edges, if they are okay then id be checking the wheel bearings.