White Regions on 1.7.8

We upgraded from 1.7.7 to 1.7.8 over the summer break. All went very well.

However a couple of times a day it appears that the Xibo Client crashes and leaves the regions white.

Any ideas?

This is in the Application Log if that helps anyone?

Application: XiboClient.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005, exception address 6B476A80
Stack:

Thanks

Jeremy