Hi, i was using the 70D for video, and to change ISO i used the "shortcut" (C.Fn III) that let you change the ISO by holding the SET button and turning the Main Dial to change the value.
now i got a brand new 80d, configured for the same shortcut, but it only works in photo mode, not video mode. (SET + Main Dial change Shutter speed as if SET button was not pressed)
It's a bug perhaps? that was the easy way to change ISO while recording video...
80D firmware v1.0.1