same issue here. PC was built maybe 6 months ago and the LEDs on all 6 LL fans worked like a jewel.... until a couple weeks ago. The most aggravating part? it randomly goes back to working as designed with no change by me. However, if i were to restart my pc or turn it off and boot it back up, only 1 fan appears to work without defect at all times. the other 5 fans go haywire, flicking rainbow vomit with no apparent pattern. 30 minutes later, I'll look over and lo and behold, the lighting is functioning properly again. Personally, i think too many of us are having this same problem in too many different configurations for it to be a hardware problem or user error. I'm chalking it up to a software problem that Corsair, while they may be working toward a resolution, refuses to openly admit the possibility of it being the software causing the issue.
PS: my problem persists through both Link+CUE2 and iCUE.
Edit: Here it is, working, just as it should
https://media.giphy.com/media/39vn71eN5gySZ2Karh/giphy.gif
