Ion XE 20 Desk Lamp Issue/Bug

Ion XE 20 desk lamp level issue.  The manual I printed out states I can change the level in the shell settings (which I can). However, there are times when I want to momentarily change the level during a show and can't go to the shell.  The manual also states I can hold down "Displays" and roll the level wheel up or down to change the intensity.  The only thing that does is change the console display screens and button light levels- It does NOTHING for the lamp level.  The manual I printed out also states you can change the level with the knob next to where the lamp is plugged into the back of the console (like the Ion consoles).  It has no knob.  My desk is less than a year old and is running the most recent software.  Anybody have the same problem???