R u restoring apps And Data through Titanium Backup after u flash a Rom ?? If yes, then that will cause problems sometimes.
How many apps are u running ?
Or the "overclocking" could be the problem.
Doesn't sound like a hardware problem at all. Flash to Stock KK4 and don't overclock, don't restore data and see how it goes. The least i would recommend is flashing the KK4 Corn Kernel version 7.0A (.tar version through Odin) and then get Root through the CWM Recovery and then remove the Bloat u don't want and then stop there and see how it goes.
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