As i said, the minimum frequency should be 1.2Khz. 1.3KHZ work fine here. So change it to...

Code:
-----[ LCD Contrast PWM ]-----------------------------------------
PWM_Contrast:
value=Contrast*40
HPwm 1,value,1300
Return

; -----[ LCD Backlight PWM ]----------------------------------------
PWM_BackLight:
value=Backlight*51
HPwm 2,value,1300
Return
About now?