1996 hyundai excavator pilot control problem

On the joystick controls the push rod will stay stuck down and will slowly come back up. This only happens on the swing function. Just changed pilot filter hoping that would do it, no luck. Wondering if there is a solenoid sticking somewhere that would cause this, or if it is all in the cab under the joystick.

This starts happening after 20 -30 minutes of operating the excavator
I took the joystick apart and springs seemed fine.

1996 hyundai excavator pilot control problem