Keyboard layout(Colemak) changed qwert


last week, I decide to change my keyboard layout, Colemak.
so I changed my keyboard layout via ibus(ubuntu 14.04).

The problem is that sometime my keyboard layout go back to the qwert.

I can solve just restart atom, but It does not mean clear.
It is impossible to notice that. to figure out the ‘moment’ I just rewrite same word again again. but only I can find is Layout be changed randomly.

when my keyboard layout chaged to ‘qwert’ in atom, my keylayout stlii ‘Colemak’ other programs. (I checked)

like I said, it solved just restart atom again, but is there way to find the reason?