flashing

Anyone have their Current LED light start flashing on and off? And, no, it's not the "lightning" setting. This is the whole fixture blinking on and off. I did a quick Google search and it seems the recommendation is to try a different power adapter. I did that....still the same. Any...

I have a mixed 75 gallon fish tank and i see no sign of ick but they flash quite often and some of them have brown ish soot looking stuff on them..does any one know what this could be....my tank have been set up for over a month the water is nice and clear, im running 2 whisper 60 filters on it...