Get yours fixed. Clicking/delayed start, and not powering on (LED either not lit or behaving oddly), opening up and inspect the power supply, in certain area where white ribbon (widest) for mainboard is near. What you are looking for is number of capacitor grouped close together all 10mm in diameter. Now inspect these capacitor's tops (aluminum with "X" embossed in them), they probably will be bulged or leaked dark stuff.
If so, these capacitors has to be replaced. Make sure tech uses low ESR 105C with high current ripple rating capacitors. Not all shops looks for this specifics as they usually buy from their electronic suppliers which is general purpose caps and this is not appropriate type and will not last and not same performance.
If your unit is warranty, which most TV are 1 year brand warranty not the "contract" type like extrended service that like best buy and such sells. For ones under warranty, these boards get replaced and this will repeat with bad caps in 1-2 years (I prefer changing caps if I care about it for reliability. For extended service coverage type beyond 1 year, "extended service coverage" contract type servicers chooses to swap boards or repair if capacitors is bulged but issues of using correct caps remains an issue.
Cheers, Wizard