^@ repeated endlessly

Hi all,
I’m running Manjaro with Linux 5.17.14-1, with Gnome shell 42.2 on Wayland on a ThinkPad p14s since some weeks now.
I previously noticed that on shutdown I saw an enthire screen filled with “^@” but everything seems to work correctly.
Today I discovered that if I switch to the console (using control+shift+3 or 4,5 etc) I cannot login nor doing anything, because this key is repeated endlessly in the background.
This is absolutely not happening in the graphical system, but I think that this is better to be fixed.

To provide a more complete information the grub cmdline is:
quiet splash apparmor=1 security=apparmor resume=UUID= udev.log_priority=3 systemd.unified_cgroup_hierarchy=0

Do anyone have any clue about what it can be?

^@ → CTRL-@ → ASCII Character Set (UNIX in a Nutshell: System V Edition)

There are NULL characters somewhere in your config files which you edited.

Wow, thank you for the diagnosis.

Do you have any clue about how to find where they can be?

…Since you are not using sddm, you can switch to using Xorg instead of Wayland on Gnome.

…i’m missing the UUID here:

quiet splash apparmor=1 security=apparmor resume=UUID=xxxxxxxxxxxxxx udev.log_priority=3

I’m using both, but the problem is present anyway.
It seems to be unrelated to the graphical system in use, but maybe with the greeter.

I redacted it as it is long and irrelevant to this problem.

On my laptop I’ve noticed ^@ appear if I’ve used the hotkeys to increase or decrease the screen brightness.

If I do not mess with screen brightness I do not see those characters appear.