Black stripes / flashing screen

Hello all,

We are using the following configuration:

* Horizon view 6.1

* Grid K2 with latest graphics card drivers.

* vdi's with Solidworks and Camworks installed

* vgpu enabled

The problem is that once a day the users screen starts to flash and they see a black stripe trough the bottom of the screen.

Any ideas how to troubleshoot this problem?

Kind regards,

Arjan