Lines on render using Vray frame buffer

[Billabong]

Our studio has recently switched over to LWF. We tried sending a render to our farm using split scan lines with the vray frame buffer and we got weird lines in our render. I don't think they are stitching lines, but i was wondering if anyone else had the same problem or knew what this was.

Thanks for any help. Image attached

[MoonDoggie]

I'm pretty sure you have to save the GI calculation before using split scan lines. (I also use an overlap of like 3 pixels).