Press one key affect other pressed

Hi I am having a trouble with the keyboard in Manjaro KDE, when I press and hold one key, for example “A” everything works fine and the key keeps sending information that its pressed. Alright, but then when I keep that key pressed and just press and release other key for example “B”, “A” is no longer sending message that its pressed even though its, in fact, pressed.
So i’m having the output of: “AAAAAAAAAAB”
I want that output: “AAAAAAAAABAAAAAAAA…”

Does anyone knows how to do this?

Obs: this is not a keyboard hardware problem because “A” is being pressed in my mouse’s side button and “B” is from actual keyboard

It’s normal behavior, you can only disable repeating or adjust speed and delay. I doubt if setting continuing repeat after press another key is possible. At least it’s impossible by default in KDE. Maybe in other DE or with specialized app (I don’t know any). Or by editing config files – but which files and how to edit, don’t ask me.