When I turn on the TV with the remote first thing in the morning I get sound but no picture. I leave the TV on with the sound on for 30 minutes and than begin to turn it off and on till I get a picture but no sound which takes a few times to get.Once I have the picture I leave the TV on for 30 minutes and than I turn it off with the remote and I have sound with picture for the rest of the day .

My 2007 Vizio JV50P HDTV10A I found at the garbage dump would turn on, make a pop sound, then nothing. So I replaced the bulged electrolytic caps on the power board with caps I scrounged off other discarded boards, and got the perfect picture in a couple hours. I used Panasonic caps? (curved T on top) FC type I believe? 1 - 10v 1000uf & 9 - 10v 3300uf & 1 - 16v 470uf & 1 - 50v 680uf, all 105c. The board had solder points all on one side opposite the cap can, so it was easy to do a pro solder job by flux & sticking the legs just barley out of the board surface.
I hope this helps somehow.
Bitdog

OUR VISIO JV50P HDTV10A does the same thing every time we turn the tv on. Their is no picture, but their is sound (sometimes). Or we might get the picture, but no sound. And if we watch certain HD channels, the sounds doesn't come in good. What could the problem be with the tv?

Does the screen look lit at all? you may have an issue with the sustainer boards (Y and Z). without taking voltage readings at the power supply board it will be hard to tell. if you check, there may be bulging capasitors on the power supply board. if so, that will need to be replaced. you can contact hdrepair for a diagnosis and repair.