I noticed that there is a "I" and an "O" icon on the left and an arrow on the right of the rectangles that include the names of the input and output of each track.  Since there is a label "IN/OUT" just above it and the scheme of the layout is flowing more or less from top to bottom anyway, would anyone miss these "helpers?"  Maybe if the rectangles didn't include them the text could be made a little more understandable?
 
Just thinking out loud.