Strips render differently using backburner and vray - needs urgent sorting, plz help

[aliadil]

We are a small new company having around 12 pcs and using the same 3ds max 2013, vray, back burner, windows 7 on all pcs. everything is the same.

 

when we do a backburner network render after the render has finished the strips in the combined image looks different, i have uploaded an image so you people can understand.

strips 7 and strip 8 look completely different and all other strips are also noticeably different.

 

so plz could anyone help in solving this issue thx.

also uploaded image of render please check, image is 1920 X 1080