Keychron K8 Function Keys

The function keys were not working properly on my Keychron K8 when in wired mode. They would only function as their desktop-environment equivalent, even when combining with the Fn key (e.g. F1 would only decrease brightness, F2 would only increase brightness, etc.).

Setting the hid_apple module option of fnmode to 0 worked.


options hid_apple fnmode=0

You can also do this ephemerally by overwriting the /sys/module/hid_apple/parameters/fnmode file:

echo 0 > /sys/module/hid_apple/parameters/fnmode

Update (as of 9 Feb 2021)

I updated the firmware on my device, and this seems to have resolved the issue I was experiencing.