FFXIV often auto-press the left Alt button (or so it seems)

Is this just me or does this happen to specific models of different keyboards? (which I doubt because I have experienced this on 3 different keyboards)

It is a very minor thing but also very annoying because it randomly chooses to auto-press the left Alt key at seemingly random moments, which could be critical in battle because you know you move with WASD key by default in this game, and when the it auto-presses, it recognizes as Alt+W and so forth.
Its particularly annoying because it is recognized as I'm pressing down on the Alt key so when I'm trying to type a chat it constantly messes with me.
This phenomenon most likely occurs after I try to type a chat in Japanese (which requires me to change my IME) because I'm on a Japanese DC and I often meet Japanese players, but its not a 100% chance that it will happen then and can happen even when I am not doing such action.

Maybe its because my Windows locale is not English?
If anyone knows about this issue please tell me about it.