DVD disks are a lot easier to read then Blu-Ray disks and TLoU is a Blu-Ray disk. The PS3 player has two separate circuit technologies to manage these differences. The Blu-Ray went out on my PS3 once while continuing to play regular DVDs just fine. I exchanged my PS3 under extended warranty for a new PS3 slimline and all has been fine for a couple years now--knock on wood.
I would definitely asap take the PS3 and TLoU to your friendly GameStop and demonstrate the problem to them. If it works 'perfect' in the store but not at your home then consider the voltage specs at your home may be off just enough to affect your PS3 but maybe nothing else?
Many gamers continue to post glitches and problems they have playing TLoU while many other gamers like myself may get through the whole game without noticing one thing wrong. I suspect TLoU pushes the PS3 design to its limits. Many seem to think the game is full of bugs--I don't.
Please post what you discover.