Hi Tony,

First try re-initializing the unit. Remember that this procedure will erase everything in RAM so be sure to save any data that you want to keep before attempting.
To re-initialize, turn the instrument off and then while rotating the TEMPO/DATA dial slowly to the right power on the instrument. Continue rotating the dial until the display reads "WARNING-Dial on Power-up requests MEMORY CLEAR". Press ENTER to re-initialize the instrument.

If this does not solve the problem, you more than likely have a hardware problem. To test the buttons and dial:
Press the General button in the Edit section, press soft button F2 followed by soft button F8 and then press ENTER. This is a special hidden screen of built-in hardware tests. In this screen you will see Panel Test at the upper right of the display. Press soft button A to access this test. Press each button on the front panel and note whether the corresponding button simulation in the display reacts. Rotating the dial should show in the upper right box 'Code: 0XOFF' when rotated left and '0X001' when rotated to the right. You can also test any pedals that are plugged into the system if you like.

If any buttons do not respond, you know that it is a hardware issue and needs to be serviced. If you need help finding an authorized service center, please let me know.

Good luck,

Dave