Without other usb devices the keyboard works immediately. With them it takes 5 ish seconds for it to start responding. This is regardless of which device is discovered first (which I can manipulate), it seems to just wait for all of them. Is there a way to make it not do that?
Edit: This is specifically about linux boot. It otherwise works fine in bios / bootloader
I had an issue where one keyboard (worked with another one) worked in bootloader, but not when entering the encryption password after that. I believe I solved that by moving keyboard earlier in the module list in mkinitcpio.conf. Maybe something similar would solve your issue?
I did try messing with the hook order but it's already as early as it can be.
Was there no option about it on the BIOS/UEFI about something like that?
You never know how the kernel would behave compared to how the BIOS is setup. There might be some bios settings that force the kernel to behave a specific way.