1st) No Sound, Good Picture. 2) Good Sound, No Picture

Hi , The link below is a YouTube page full of videos showing how to fix a Vizio television NO picture GOOD sound, I hope this helps....... CHEERS..
Vizio Tv With No Picture Good Sound YouTube

sounds a lot like you lost the video driver or control board functionality. From the 'decay' of your image, with sound still working, and all else being good, you're primed for a new video controller. Are you inclined to do the repair yourself? The service manuals are hard to get online, but the local service center MIGHT sell you one.

the main board will need replacement. Audio signal are produced on the main board so replacing the main board should solve the issue. You can get replacement main boards from www.tvcircuitboards.com

looking online as i have same problem, sound without picture points to T CON board. approx $50-100 part + labor

Is the TV under warranty? If it is don't muck around, contact them straight away as you have a electronic problem with your screen.
Before that make sure the yellow chord is in the visual port and red and white into sound. 2) If thats all good try an experiment, as you know the sound is good, use one of the sound cables to replace the yellow. Is there a picture now? If so replace chord, if not make contact to exchange for warranty.

The sound amplifier IC has went bad and needs replaced. Call a good TV Tech.
Check with the BBB 1st before you decide on one.

Your audio switch on the back may have gotten moved please check the switch

LG tv flatron no sound, picture everything else is fine but no sound what can be done to fix it

can you see the g2 from crt sound like you list your g2 from
the flyback.i need m# plz

I have a sansui 19" LCD TV+DVD
I had to attempt multiple times turning the TV on to get a picture. The sound was fine. This kept happening when I would go to turn on the set the TV kept playing fine with picture & sound but after the 2nd attemts I turned it off & then tried to turn it back on which took multiple attempts, it kept playing for a few minutes then the picture went out but the sound was still there.
The set is not yet 2 years old.