Just started the CTC-3 tutorial. When driving the train at speed. It is horrible to listen too. It sounds like tap has been left on. Or one of those kettles you put on the hob to boil water and just making noise. I find it very off putting and most likely will not be driving it again. The outside cab sound is fine.
Try putting the headlights to dim. I've noticed with the headlights bright you get that high pitched whistle.
When I put the headlights on bright I heard the high pitched noise, like a frequency generator. After gaining some speed though this is drowned out by wind noise.