Unfortunatly your vehicle has an issue with water leaking onto the amplifier, and causing symptoms similiar to yours. You'll most likely need to replace the amplifier, and install a water shedder over the amplifier to prevent another failure in the future.
Okay, thanks. Where exactly is the amplifier located in the Range Rover?
The amplifier is located in the left rear of the vehicle behind the trim panel. It's very easy to get to.