I have a samsung s9000 tv 13 months old and it has recently developed the following intermittent fault,at power up the bottom right hand quarter of the screen flashes light & dark no matter what source the set is on, putting the set into stand by does not cure the fault, but disconnect the power and power up again and all will be ok maybe for a day or a week or even 4 weeks but it always goes faulty again. the set has been back to dealer who says all is now ok but 4 weeks later it started the same fault again, The only ever happens at power up,it has never happened during watching any source Iam sure the dealers engineers put it on soak test and as the fault did not occur the boxed it up and said all was ok/ Any advice please

If it's still in warranty then I would have thought they would offer you a replacement if it cannot be fixed.

Would don't you film the fault next time it occurs, so you have some evidence to show the dealer?

Do you mean the JS9000? It's a curve screen with nano crystal technology (called quantum dot this year), its got the one connect box.

Sounds like dead/dying pixels to me. It shouldn't happen on top of the range tvs this soon. It should be covered by warranty. That tv had atleast 5 year guarantee from most retailers. If it's 13 months old and is the JS9000, it'd be the first batch and it did have issues, most notably in the 65 inch.