Reflection gives lines along mesh polys

Unity Engine
1

Hi forum! I’m having an issue where adding a reflection probe will draw these lines for all the polygons in my model (see image). It seems to only show if I add a metallic map, and goes crazy if I add a normals map as well. I’ve tried changing settings for the probe resolution, the texture maps, and different metallic/smoothness settings for the materials. The lines disappear when looking at the object from certain angles, or when removing all textures except diffuse.

It’s being built from Unity 2018.3.3f1 on my macbook, onto an iPad 12.9 Pro. Using the ARKit 2.0 unity package from their git repo. The lines don’t show in Unity, only on the iPad Pro.

Anyone recognise this or have an idea on what it could be?

Thanks!

4460764--409405--polylines.jpg
4460764--409405--polylines.jpg1406×1251 237 KB

2

Update: I want to add that this happens on any mesh, I’ve tried the built in ones and also imported different FBX models. It seems to appear as soon as you add either a metallic map or normal map, while also using a reflection probe. Removing the reflection probe or the metallic/normal maps, will remove the lines.

3

Update: If the mesh receives shadows it happens as well. So I guess anything being blended on top of the diffuse and reflection maps give me these lines. It’s as if the vertices are not welded.