Playstation can't read backups

[zarquon]

I've recently installed a modchip in my nephew's Playstation, but can't seem to get a backup to actually play. Most of them lock up at the black Playstation boot screen, a couple will play the intro movie, but lock up at the actual game, and one, just one, actually works. They all work in a Playstation emulator on my PC. I've tried Fuji, Sony, and TDK blanks, burned with CDRWin, Nero, and BlindRead, at 1x, 2x and 4x. I've even tried messing with the laser power adjustment in the Playstation. I'd think I installed the modchip incorrectly, if not for the one that does work. Any thoughts..?