for me it's the "reload" button, tried to set it to a different key, but no chance to remember that during infight action. playing shooters since wolfenstein 3d and "b" has always been my reload key (i'm a lefty, moving with zghj)
really doesn't make any sense to have "open console" hardcoded to a key exactly in the middle of the keyboard. why not open/close with tilde, or at least move it to F12 or something.
however, i've also contacted @AskEASupport on twitter and they claim DEVs are aware and looking into it. let's hope it's true and that they come up with a reasonable solution.
EA Support on Twitter