Tv comes on flickers for about 10 seconds then picture goes out. sounds stays on.

Chances are your main board is defective and needs replacing

in the back of the t.v. there is a mother board. on the mother board ( im not sure what it is called so i will describe it)
it looks like a black tune. it has a red wire comeing out of he top going to the front of the t.v. connecting to the picture tubes. now see what happens is that tube will heat up and sometimes loose connection. what i found to be helpful is to stick a peice of cardnpard under it so it gets a good connection again. but do becarful because it is high voltage....... so if you decide to try to work on the t.v. please unplug it first.

i'd say your tv is unhappy.

unplug for 10 min..and see if that resets it.

Try a hard reset to this set, and check. There are two types of reset to TVs. The first is simple to do; a Hard Reset. The other is somewhat skilled; is a Factory Reset (System Reset). To make it a hard reset, just unplug the TV from AC mains wall socket, and re-plug it back after 15 minutes or so. If you do this by overnight is better. This procedure will make it a hard reset. If you want to make it a system reset [Factory Reset]; you have to enter its service mode option, and select the factory reset option. If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/
Service mode entry, adjust and exit procedure to many popular brand TVs are given. Never forget to exit the service mode, after all adjustments have been done.
If the reset do not help you, its main digital board is faulty. Check and replace it.

Not sure right off bat, however unplug it from the wall for three or four minutes plug it back in it might reset it?

The tv have LCD inverter boards backlight problems,tv is new take it back where u bought it for a new tv replacement.

Hello,

try connecting tv to cable direct also try unplugging both converter and tv for wile like 5 mins plug both back in see if tv and converter sync, but if otherwise then
The ysus board is the most common reason.
you can try websites on ebay.com to buy parts for replacement...

Sounds like the digital board needs replaced.

Try a "hard restart" , which simply means unplugging the power cord of the TV, then replugging it after 4 hours have passed. This technique helps to reprogram the electronics of the TV.
Hope this suggestion works for you.