I’m having a problem with my new spec d headlights. When i turn my headlights on (not auto headlights) SOMETIMES both the bulbs turn on. I turn them off the back on, only the left one turns on, turn them off, then back on, only the right one turns on. Anyone know a solution to this? Or why it’s doing this?

 

Are these the headlights that take the stock ballast and bulbs?
I'd start with double checking connections, wires, grounds.
Then, if the problem persists, maybe swap ballats/bulbs side to side. See if the issue swaps as well.
if it's a problem with the built in LEDs, return them as faulty.
good luck!

 

I have a 2014 Infiniti q60, I also bought the same Spec D LED lights, and I’m also having this same issue. Have you been able to find a solution, or at least found the issue?
I have the stock ballast, and the stock bulbs in.