That was going to be my response too. I'd connect the ground to the "earth" pin too.
It worked! I connected pins 3 and 4 to a female composite jack and now it displays composite video! Now all I need is a 3.5mm to RCA adapter.B.Goode wrote: My, 'try the simplest thing first,' approach would be to connect the composite video output from the 3.5mm jack on the RPi to the Composite In on pin 4 of the monitor.