The webcam camera has an automatic volume control on its microphone. Without a steam train pounding up the 1 in 49 into Goathland station, the microphone becomes very sensitive, and the sound of the water flowing nearby is rather amplified. It doesn't sound nearly so loud when you are standing at the end of the station platform!
This is the stream:
Looking down in to river from bridge to railway station
© Copyright
Nicholas Mutton and licensed for reuse under this
Creative Commons Licence.
Looking downstream - the station and the webcam are a few yards to the right of the photographer's location. (Click on picture to go to the larger original.)