Im having a similar issue, Icue doesn't seem to pick up either my keyboard or mouse on boot (sometimes one, sometimes the other, sometimes both). Unplugging them and plugging them back in seems to work (go figure). Firmware on both is up to date, Icue is up to date and I tried a reinstall which worked for 1 reboot, then it went back to hit or miss detection. K70RGB quickfire + Scimitar Pro RGB, Win10 Pro slow ring insider. Not sure if relevant but I'm also using a Corsair cooler H100i v2, which always gets detected properly but occasionally cranks everything to 100% for a short time when I boot, despite temps being well under the threshold set to do that.