Hi all, I'm due to take my 2015 Civic 1.6TD Sport in for a service but have a couple of long journeys to do in the meantime and have noticed an odd noise that I can only describe as similar to the noise rails make when a train is approaching. It's difficult to pin down as it's a little irregular and isn't consistent with braking or acceleration. Just wondered if anyone had any ideas before I sound like an idiot trying to explain this to the garage! Thanks all!!