I thought a lot of complaints had come about due to the so called "new horns" installed in more recently built classes being louder. I don't know that they are louder, though a 377 does sound much louder than a 319. Can't think why else it would have recently become a problem. I was quite impressed with NR trying to be a good neighbour policy, not sure I would have been so understanding with the residents. 
On the Swanley - Sevenoaks (via Otley) route we were told when route learning that a Whistle board had been removed due to complaints from residents. No idea if it was true though.
On the Swanley - Sevenoaks (via Otley) route we were told when route learning that a Whistle board had been removed due to complaints from residents. No idea if it was true though.