Actuator 6V works on PWM, 12V doesn't: aarch !

zoomkat: only one of my 2 12V actuators do still work, so yes I probably fried something

Well, if you had the below R actuator version, the actuator might act like a servo. You said you hab the I version which doesn't fit with connecting a control signal to the white analog output wire on the actuator. Good luck!

R RC Linear Servo. Not available with 10mm stroke or 12 volts