Two things from someone who’s been driving trucks for over 30 years and does still drive every day of the working week .. <br>1- I’ve never heard a single truck make this noise anywhere    And <br>2- So if a truck turns up to a cross rail site and it makes the wrong noise it’s sent away ? <br>Well that’s great then for the environmental impact isn’t it.. a totally wasted journey, possibly hundreds of miles if a special bit of kit is being brought in just because some twat in a office has decided to use a different type of buzzer... way to go TFL ..