Is my Samsung Fault Covered?

Hello, My Samsung LE40R73CD does not suffer the clicking noise / not switching on issue. It switches on but after 5-10 mins the screen goes blanks but the sound stays on. If I switch off and leave for a few minutes the picture returns but goes off again after 5-10 mins.
My concern is if Samsung may wriggle out of their committment to recify thier manufacturing errors.
The TV is now with an authorised repairer as instructed by Samsung, but despite me making clear the fault the repairers thought they came to fix a clicking fault. They tell me it's a backlight issue which is a power supply issue or control issue so I am now not assured about the TV being fixed under warranty. If anyone has experience of the extent of Samsung's committment I would be grateful for a response. Needless to say I think Samsung should go completely out of their way to restore faith. We are using our secondary older HDTV in the meantime, a Sony which has never missed a beat.