As I understand it, repeated presses of the "check 6" key should move the selection from friendly to friendly (sometimes it does), and pressing "check 6" when there is no friendly in the view should cancel the selection. However, often the check 6 call selection will fix on one player and won't move to others when I continue to press the key, and if I switch to a view with no friendlies it will still "call" the player that was selected. Maybe I'm doing something wrong.