hmmmm.......just curious ..... why are you "rolling" in neutral..??
Does it do it with the clutch in & out or just one way .. ??
As far as your questions, I's say:
1 - mine doesn't make this noise (of course I'm old and half deaf)
2 - I doubt it
3 - oh, yes ....especially if your half deaf
4 - sorry, I have no idea
I hope you get it figured out ......
humfrz