white screen on web page refresh

Hi,

I have installed the licensed XIBO Android client on one of our displays on campus.

The display is located across from some administration staff, and they've notified that a white screen flashes across the display every so often, and it is causing a small distraction.

The layout design consists of a region "Webpage lasting 600 seconds", so it's definitely the XIBO client webpage refresh that is the cause of the issue.

You can also notice the white background when you start the Layout Preview, and also every 5 minutes during the page refresh.

Is there a way to change the white color to something else? I thought that setting the background color of the layout to #000000 would solve the issue, but it persists..

Any help would be appreciated.

Thank you

Regards,
Justin