2007 radio *Audio Control" doesn't work

I have a 2007 Toyota Tacoma the radio audio control button only adjusts the channels.
No matter how long or many times I press the button, it does not allow the adjustment of treble, Bass, fade, etc. Before I pull the unit out and take an ohm meter to it, has any one come across this and have a less invasive fix?

 

Do you have a picture of the radio in question and what button you're pushing? On my '08, you would push in the tune knob to cycle through treble, bass, etc, and the tune knob would adjust the setting.

 

Yup, I have the LS1808 radio and the manual says to do just what you say you do. The tune knob does adjust the frequency but when I push the knob, nothing happens. It never cycles into the treble, Bass adjustment mode.