I'm new here, so please bear with me while I get settled in.
As of yesterday I too have started having this problem, but it only started after I updated to the latest version of the software - v4.11.274. However I must add that it was purely coincidental and the software is not to blame (at least not for me). As it turns out it is one of the LED's on one of my fans that has died, which is causing the crazy flickering. I found an easy way to test which LED it is - as follows:-
1. Using the iCUE software click on Lighting Channel 1 - in my case I am only using one channel (If you are using 2 channels use the following steps on each channel)
2. From the Custom drop-down list select Static Colour - using White
3. Click on one of the LED Port images - you should now have only 1 LED on and all the others should be off
4. Click on each of the LED spots on the LED port images one at a time - if you have a bad LED it will show when you click on the spot of the bad LED
So it looks like I shall have to buy a new fan - although it should still be under warranty.
Edit - Just cleaned up some spelling mistakes
