Unplug ALL HDMI cables. Then remove power from the unit for 10 or more minutes to let the HDMI chips reset. Apply power, use the Fire TV HDMI cable and re-test.
My samsung TV says no signal when trying to use my Xbox or computer on it. I've tried each HDMI port on the TV and I've tried multiple HDMI cords, and both devices work on my old tv. I've tried resetting it to factory settings and I've tried unplugging everything for 10 minutes then plugging it all back in.
My fire tv works fine on this tv, but the Xbox and computer say no signal.
Anything else I can try?
Thanks

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