My used XJ8 VDP arrived today, but unfortunately did not include any manual on the rear entertainment system. We're trying to see if the audio from the DVD can be heard through the audio system speakers, or only via headphones. We have a young son and will need to hear what he's hearing. We've tried turning the Headphones Only feature off, but there isn't any way to do so without turning off the entire DVD. Is it possible Jaguar had it as an option that the original buyer didn't purchase? Seems odd, but that's the only thing we can come up with.