My amp keeps getting REALLY hot..?

Like, you burn your hand when u touch it. It's a Legacy Predator LA-2268. About 900 watt rms, running 2 12 inch kickers 400 watt rms each. Wiring from subs to amp is 8 gauge. Power cable and ground wire are gauge 1. Hooked up to 5 fared cap (dont need it, I know, I just haven't got to taking it out yet). Head unit is pioneer 50 watt 4 ways. So does anyone know why it keeps getting really hot after running it for only like a half hour.