Volume control buttons on steering column do not work. on 2006 Lexus LS430

I have the navigation system with the Mark Levinson stereo. The volume control on the center console works fine. The steering column control button will change from AM to FM to CD etc. It will not control the volume at all.

Asked by for the 2006 Lexus LS430
the button may be worn out inside cover that is common on all these type controls
Thank you again.