Gear VR - some textures directly in front of Camera Rig blur in the middle

I'm having this problem that's only visible when deployed to android that particular textures (not all) are afflicted with a blur right in the middle of the viewer focus, but not around the edges and only at a close proximity to the camera, it's like there's a vaguely diamond-shaped blur patch in the middle of the viewer focus.

All textures are using ASTC compression, the same shader (changing the shader does not resolve the issue) and are on FBXs exported from Maya.