I agree with Fless. Swap the LEDs, in order to pinpoint if it is the LED assembly itself, or something else.
My JDM Astar LEDs have two components, the LED light piece itself that inserts into the headlight housing, and a transformer unit that connects to the stock wiring plug and the LED light piece, and they are connected together by a disconnectable plug. So, in my case, if I had to troubleshoot my LED headlight assembly on one headlight, I'd have to troubleshoot each component, one at a time, through individual component swaps to the other headlight.
I suspect that you may need to do the same.