HDMI blinks when its handshake fails. You can try other HDMI cables but I find many consumers to counter with "it works with my Xbox" and are unwilling to pay for our tech to go out to try a new cable. We use those Amazonbasics with no issues.
If that fails, try the old unplug everything from the tv, including power and wait 10 minutes. Now apply the AC then the lone HDMI connection and if it fails the two devices are incompatible.
HDMI is not consumer friendly. It has HDCP and when there are issues you find most companies feign ignorance of the issue. I won't.
Bob
We have a sony bravia LCD tv, model KDL-60EX500. It's 26 months old. We have satellite TV. 3 weeks ago we had a window stating "Hard drive failure" of the satellite receiver. The satellite tv company sent a new receiver, which we installed. The tv then started "blinking" on and off - no sound, black screen - for a half second or so. It was happening every few minutes. The satellite tv company sent over a technician, who replaced the new receiver with another new receiver. Same problem. I should mention we have a second,old, non-HD tv running off of the same receiver box. No problem with the second tv.
I switched HDMI cables. No difference. I switched HDMI inputs into the TV (there are 4 of them), it made no difference. The blinking happens on all 4 inputs.
I switched to the old style component cables with male ends, using the "component 1" input.
It works. No blinking.
I use HDMI to connect my blu ray player to one of the HDMI inputs. There is no problem when using the blue ray player, but if I switch that input on the tv and hook the satellite reciever to it, the blinking returns.
Summary: the satellite feed for TV reception causes "blinking" on any of the 4 HDMI inputs, but not on the component feed. The 4 HDMI inputs do work for the blu
ray player and for a "wii" we have connected to the TV

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