With the Windows OS embed player application installed and running on the device, carry out the below steps:
Press CTRL+Q, ESC or right click the mouse to bring up the settings panel:
Enter the default password then select the yellow 'Settings' button
Next, you'll see the display available on the device - select each one so it's highlighted in blue and then click the 'Apply & Save' button
You will then be taken back to the password panel where you can select 'Done'
The app will now be running over the selected displays and when it nexts checks in to the CMS, you'll see the device resolution has updated to show the full output.