I am a native New Zealander myself. Coming back to NZ this time I was struck by the difficulty I was having in understanding ordinary speech.

New Zealanders are inclined to drop the fina consonan of wors.

But more confusingly, every vowel sound (with the exception of the eu dipthong – as in duel – and the long a – as in way) collapses into a neutral ‘uh’ sound.

Thus muns yuh und up wuth suntunsus thut sund luk thus.