HDMI cutting in and out.

SOURCE: Westinghouse 1080P 42" LCD TV - HDMI stopped working

Just reset the TV found out how here: http://www.danielcoburn.com/uncategorized/westinghouse-1080p-42-lcd-tv-hdmi-stopped-working-fix/
Hold the power button for 10 seconds.

SOURCE: my hdmi port is not working

I have Verizon Fios and there's a known issue with the motorola HD boxes that they have bad hdmi ports, the screen goes green and that's it, nothing I can do about it I just use component cables. You need to be sure it's your tv not the cable box. Try the hdmi on a dvd player or ps3 or whatever else you have first just to be sure it's the tv at fault not the cable box. If you determine it is the tv you need to replace either the main board or the video board depending on your specific tv model. Some have the video inputs on the main boards some have video boards.

SOURCE: My Bravia KDL-40S4100 lost all 3 of it's HDMI

There is a problem with the processor. The only way to resolve this issue is to replace the main board. It is called the A board in your TV.

There are two for this model and the correct one will depend on what your serial number is.

Part numbers are as follows:
part # 185709211 for Serial #
1,000,001 - 1,350,000
1,700,001 - 1,750,000
1,800,001 - 1,804,270
1,804,271 - 1,818,372
1,818,373 - 1,830,000
list price: $504.87 core charge: $680.00

part # 185709231 for all other serial numbers
list price: $505.87 core charge: $600.00

Testimonial: "Thanks, Now I wonder who all shares the same problem and if Sony is willing to do something about their defective products..."

SOURCE: I cannot get the Input

input is shared with component input--one or the other --must choose in set up menu

SOURCE: no hdmi signal on a panasonic viera tv, they used to work

sounds like you need to update firmware