henryn2,
There's no sensitivity adjustments for the HDMI ports. It works a little like USB, in either it's connected and passing data, or it isn't. If everything else is working properly without issue in the other HDMI devices, you may want to contact Verizon to get a box that may better connect.
When you say it works "intermittently", do you get audio with no picture? Or a Signal Not Available message?
--HDTech
Have had a PN58A650 for about three weeks now and love it but for some reason it fails to detect my HD Cable Box from Verizon FiOS (Motorola QIP-6146-2). It detects the box intermittently. I've tried different HDMI cables and all three HDMI ports on the back of the set. When it fails to detect the box I have to hard start the box (unplug power cords and plug back it). It then will recognize the box and work fine for a while (a few hours or a day or so).
Is there a sensitivity adjustment for the HDMI ports? The HDMI ports recognize all other equipment I have.
Anyone else experience this problem.
Checked latest firmware version and it's 1006. Set manufacture date was 31 Dec 08.

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