Flickering black screen LG 37LC2D-EC

SOURCE: LG 42LC2D-EC NO SOUND ON HDMI

your setting for source of the audio is probably defaulted back to original setting in receiver. reassign audio input and problem may go away. it sounds like its not in the tv. i assume you have a receiver and are not trying to listen with speakers in tv. is this correct? if you are not using an amplifier, you may need to go to the tv menu to make sure the audio source is selected as the hdmi input. should take a bit to read thru the manual, but it ought to show you how to accomplish the correct settings.
let me know if it does not.
good luck
mark

SOURCE: Connecting to HD TV

This TV has no HDMI input socket. It Has a DVI input socket. Therefore you will require an HDMI to DVI converter adapter or an HDMI to DVI cable. The DVI is video only so you will require audio cables from your Sky box (Audio L and R ) which will connect to the back left of your TV (Audio L/R sockets next to the s-video and component video connectors)

SOURCE: LG 37LC2D-EC

It sounds like the TV is having sync issues with your Sky+HD box. HDCP is the "High-bandwidth Digital Content Protection" that is used between components. It requires a sync between the devices to ensure that you are not trying to "steal" the video content you are watching. This intermittent message and blacking of the screen is good evidence that this is your problem.

Even though the HDMI cable worked fine on another set, I'd try a new one anyway. Some TVs and components are more sensitive than others, and a weakened cable may not show a problem on one set, yet show it on another.

Barring the new cable not working, check LG's website for a possible firmware update for your TV, and also try using a different video source, like BluRay and see you have the same problems.

Beyond that, it may just be an issue with the TV itself starting to die.