You can test if this truly is CEC or if it is your TV by disabling CEC altogether on your Pi.
Set the following in your config.txt to do this:
hdmi_ignore_cec=1
Note the difference from the similar …init=1 option which only disables CEC on boot (when Kodi starts it will be enabled).
However, if your TV supports CEC you should be able to disable CEC and optins in Settings - System - Input devices - Peripherals.
If this is not available, try to switch skin and reboot.