Yes. It is a wired keyboard. I am using a KVM, but I have also tried connecting a usb keyboard and a usb mouse directly to my Mac mini, and it still won't go into safe mode. I also unplugged the external backup drive. However, I did not plug my 2 displays directly. They are still on the KVM and I switched to another computer while my Mac mini was booting up.
Please help me out. I have no idea what else to do. I have thought about doing an Option C or Option R, but I think what I need to do is clear the caches by going into safe mode in order to fix that my Mac mini is running slow.
I have looked at the activity monitor. The CPU is not under heavy use. I can't tell whether the write and read to disk is normal or not. I tried logging in from a different user account. It's still slow using a different user account.
Also, I think my Mac mini tried to restart itself while I left it on.