Unplug all cables, power and let it sit for hours then try again. Any component inputs?
So My old LCD has a problem with the HDMI ports.
All other ports seem to work.
Iv checked the sending device and changed resolution. It also works good on another samsung tv.
Iv booted to reset mode(Info-Menu-mute-power) and disabled and enabled HDMI ports, no go.
In the main meny the HDMI ports are grayed out. Also forced tv to HDMI 1 and HDMI 2, but no go.

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