Delay for shorctut context when switching split panes

I'm using two panes (splits) to edit code in qt creator. The problem goes like that.

1. I have cursor focus in the left pane
2. I click somewhere in the right pane with the mouse and the cursor appears there
3. I immediately press keyboard shortcut to switch between Header/Source
4. The Header/Source switching is made in the left pane, and the cursor focus goes back to the left pane.

If I wait between point 2 and 3 around 1 second, it works OK.