Ctrl C doesn't leave insert mode

[djm30]

Hi everyone, just installed the extension and trying to learn Vim with it.
Whenever I'm in insert mode and try to exit it using either Ctrl + C or Ctrl + [ , it doesn't work, the only way I can leave is via pressing esc. I have the Use Ctrl Keys settings enabled.

(Ctrl + C still copies as well)
I'm running on ubuntu, thanks.