Kenwood KAC-9103D Car Amp

This amp was good when i had three kicker 10s and it stayed cool and never shut off. it wasnt loud enogh so i bought one old stroker 15. it is louder but that one speaker at one and 4 ohms trips the overload after 5 minutes of moderate play and heats up the amp.I have heard the audiobahn 1300 watt peak amp with two twelves make my tonsils move and hurt my throat but this doesnt come close it gets hot, but doesnt trip. i dont have testing equiptment but i think it is over rated by 200% Also the amp wasnt working at all and i almost returned it. i moved the phase switch and it played again.