OS: OSX 10.4.3
Software: Blender 2.79b
ProRender version: 1.8.253 (core 1.321)
Issue: Different rendered output when rendering with either CPU, GPU or CPU + GPU.
Pay attention to the light passing through the glass spheres, noticeably much more light passing through on the CPU only render, this is with caustics disabled in the shader/material. I've also done the same test with caustics enabled, still quite a large difference between each render device mode.
Attached packaged scene file and images.
