Mental Ray Batch Render issue

I have a problem with mental ray where my batch renders will have random frames with no image in them at all.
For example. i've done a few animations of of varying sizes anywhere from 50 to 360 frames. and between the four them if i check the folders i render out to some frames will be blank. i'm using EXR's and i didnt have this problem on the last thing i rendered using VRay.

It's very frustrating, as i have no way of knowing if a any given frame didn't render an image without going into a finder window and checking each frame individually.

The problem is, it's only like a handful of frames like 30 out 350 in the current project i'm working on. I would be done if I could get all the frames to batch render correctly.

Thanks for your help