All X-SBL monitors have the bonded screen to reduce glare. Maybe the monitor is not set for full sun work.
First make sure that it is set to full brightness: press the 1st steel key bottom left corner of the screen until the monitor is set to FULL BRIGHT (it should not be in STANDARD CALIBRATE nor in USER 100%).
Then go to the main menu, choose INPUT PROFILE and change from REC709 to LINEAR.
Finally you can also play with the BRIGHTNESS and CONTRAST via the ADJUSTMENT steel key. All is set to mid-range by default.
Any flat smooth surface will become reflective in the sun at a specific angle, wether it is made of glass or metal. That is why the CRTs were convex. With all the flat screens however there will be a specific angle where the screen becomes reflective, but that should be only a few degrees wide. So far the few hundreds users of the X-SBL monitors have been able to tilt the monitor by a couple of degrees in one direction or another to prevent this. If you mount your monitor at a 45º angle and at that specific time of day the angle with the sun makes it reflective, try to set it to 43º or 47º.
I hope this will solve your issue.
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