render with network render

Hi,

I m currently working on an animation rendering under Cycle. I use the pluggin Network Render to launch the renders on several computers plugged in a local server.

The issue I am having is that the computers randomly stop rendering one after the other and I cannot figure out why.

Does anyone else have this kind of problem? Any advice?

Render: CPU
Blender version: 2.76
Windows 7 for all computers

Thanks a lot!