Win 7 SP1
There's something wrong with the way Blender handles driver related rigs. In the scene that I'm working on, I linked the "HATCH" object from the file "HATCH.blend" There is simple transform driver based opening and closing rig system on it. I uploaded this one to RenderStreet (http://render.st) to render it out, and when the frames started coming out, I saw huge motion blur on the hatch, which was supposed to open rather slowly. You need to pack your blend files before uploading to RenderStreet, so the hatch in the scene I'm sharing with you is embedded, rather than linked. But it matters not, because when I opened the "PL10_RV01_01.blend" file, in which a proxy was created to animate the hatch rig, I found that when you rewind, the hatch is ill-responsive to the animation on its rig. Only when you click on the go to first frame button once or twice, does it respond correctly. But the nodes on the render farm see this as a huge jump, hence the huge motion blur. What gives???
Way to reproduce this:
1- Download the files from https://dl.dropboxusercontent.com/u/28170294/PL10_RV01_01.rar and Open the "PL10_RV01_01.blend file"
2- Locate the packed "HATCH" object. You can also solo its layer.
3- Playback the animation, you'll see that the driver driven location of the object is not consistent.
4- Press the Go to first frame button, you'll see the inconsistency even better.
5- I'm also sending the source blend file named "HATCH.blend" for you to check out.