Screen backlight and PWM

We have put the screen backlight (we are using our own version of the UD700) on pin 130 which is PI7. If I configure it to use straight GPIO everything works great. It also dims correctly when I configure it on PWM (PWM8.3). However, when configured for PWM, I get continuous touch_up events. Any thoughts ?

Noise? Try adding some RC on power lines and pwm

Try a lower frequency