Displays black frame or distortion

Ｑ1：Why are there black borders when connecting my smartphone with Gechic monitors?

📌Ａ：The black borders are caused by the output format of iPhone/Android phones. The black frame is caused by the output format of the iPhone/Android phone.
The black border may appear on the left, right, top, and bottom of the screen because the screen cannot be completely filled up under the principle of equal scaling of image.
For more details, please refer to this article about the black borders of iPhone application.
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Ｑ2：The screen is distorted when I watch a video with my phone & Gechic monitor.

📌Ａ：Please enter the OSD’s “Aspect Ratio” setting. And then turn off “Overscan” to solve the problem.