Your last point about it staying on is the heart of the mystery. All the LR stereos have an odd relationship with their cd changers. The changers are in loop with the head units. Check the connections at the changer. If you do decide to replace, I would grab another factory unit off ebay. Hate to see a Range Rover interior get messed up with aftermarket stuff. If you do go aftermarket, I suggest using Crutchfield.com. They can also provide wiring adapter that will plug right into the factory harness and retain steering wheel controls.