SW2016-Appearance un-mirrored when rendered

Hiya,

I've come across a strange problem.

When I apply an appearance to a face on my model in SW2016, everything looks fine. It is mirrored it both horizontally and vertically.

But when I render it in PV360, the mirroring seems to get "turned off" and the appearance gets flipped back and obviously looks wrong.

Has anyone seen this before? Is there a fix?

TIA.

SolidworksPhotoview 360