russrahlanswered grow question 4 years ago I have some spots like that on my King LED 1200w I’ve been running for a few years now. The led inside seems to work but the plastic bubble shield covers over a few leds have burned black over time. Think it is just heat releated and the fact we run them 18hr strait sometimes, day in and out. Mines not under warranty anymore so I just use it for a backup light. But if yours is still under I would contact Mars hydro for sure. Cheers!💨