Noises from the front of the eNV200. 

Sometimes it does, sometimes not. 

Usually first thing in the morning when setting off.
Almost silent at first (low speed)
Never starts making the noise when driving, 
With 'ignition' on or not, eg rolling down hill in neutral
Nothing when stationary, 
No perceptible rolling resistance
Speed related and louder when faster, but not load related
I suspect the sound is from near the  D,N,R 'gearstick'.