Have you tried this:
Adjusting the response positions of the touch panels (Touch Panel Calibration)
If you feel that the touch panel keys on the screen deviate from the actual positions that respond to your touch, adjust the response po- sitions of the touch panel. There are two ad- justment methods: 4-point adjustment, in which you touch four corners of the screen; and 16-point adjustment, in which you make fine-adjustments on the entire screen.
! Park your car in a safe place and use this function. Do not operate it while driving.
! Touch the screen gently for adjustment. Forcefully pressing the touch panel may da- mage the touch panel. Do not use a sharp pointed tool such as a ballpoint pen or me- chanical pen. Doing so may damage the screen.
! If the touch panel cannot be adjusted prop- erly, consult your local Pioneer dealer.
1 Turn the unit off.
Refer to Basic operations on page 14.
2 Press and hold HOME to start Touch Panel Calibration.
The 4-point touch panel adjustment screen ap- pears. When 2-point appears at once, touch both.
3 Touch each of the arrows on the four corners of the screen.
# To cancel the adjustment, press and hold HOME.
4 Press HOME to complete 4-point adjust- ment.
Data for the adjusted position is saved.
# Do not turn off the engine while the data is being saved.
5 Press HOME to proceed to 16-point ad- justment.
The 16-point touch panel adjustment screen appears.
# To cancel the adjustment, press and hold HOME.
6 Gently touch the center of the + mark displayed on the screen.
After you touch all the marks, the data for the adjusted position is saved.
# Do not turn off the engine while the data is being saved.
7 Press and hold HOME to complete the adjustment.
Just an idea.