Paddy,
According to the preference Pane, the mouse batteries are at 54%. So that's not the problem although I will install new batteries. After 55 years working with electronics nothing surprises me especially trusting a software "meter".
XABD,
The Magic Mouse does not have a scroll wheel. I tied everything including a soft touch, a hard touch, and throwing the damn thing against the wall. For the latter, nothing happened except the mouse sulked for a few hours. I also tried washing my scroll finger and then dipping it into alcohol. Again nothing happened. The scroll works via a capacitive effect and it may be at my age (77) I don't have enough electrostatic charge!
I did tried rubbing my hand on my cat and also shuffling my shoes on the rug. Didn't help. So tomorrow, I am off to the doctor where they are going to hook me up to an electrostatic sphygomometer. The doctor did warn me that lack of charge could be due to a genetic effect or to old age.
MamaMoose