The 4K refers to the HDMI inputs signal only.It supports up to 4K 30Hz in and 1080P 60Hz out. Pls set the resolutions to 1080P. Up to 13 Display Modes: This 3x3 video image processor can connect up to 9 LCD TVs or other displays, which can support multiple display modes, such as 3X3, 2x2, 1x1, 1x2, 1x3, 1x4, 4x1, 3x1, 2x1.
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