I have this LED light which started blinking under some use. So, I desoldered the SMD LED component and hooked it up to a variable power supply. When I apply 6V, the LED starts to emit a little bit of light as expected. But, as I ramp up the voltage to around 7 volts, it starts blinking and as I increase the voltage further, it stays off more. At 12 volts, it becomes just random flashes. WHat could be causing this?