I had this same issue with my k70 keyboard and had opened a support ticket back in october of 2020. Back in Jan of 2021 I received an email from JosephN that stated "I am glad to announce that we will be releasing a firmware update within the next month that should resolve this issue you are having". The issue seemed to have been resolved until I updated to icue 4.20.169 this morning and now the problem is back.
Keyboard works fine after you disconnect it and login to the mac desktop (and once icue loads), then reconnect your keyboard.
I do wish there was a bit more mac testing with these products/software given the claim of support on their site.
