3D Cave - stereo issues after Windows Update

Hi all
This is from an Autodesk distributor after installing a 3D Cave for a customer;
#We have a problem running Stereo at a customer cave. Some months ago they run a Windows update and all driver settings were lost. Even the Mosaic settings were lost. We now have everything up and running except stereo.

-Technical info
The Cave is a four sided cave with 3 walls and a floor.
PC has 2 K5200 with SLI.
The Optoma Stereo emitter is connected to the DIN port.
Unity is used to build “games” that we run.
You will get a built example to test if requested.
If we run the 2.exe we get a mono presentation. And if we run “Stereomode.exe” we should get Stereo., But all we get is a crash…
I have tested more or less every setting in the drivers without luck."

Any insights appreciated