Thank you Technotiger - a new mouse and there's no fluf anyway but thanks. Thanks Graham, Sorry, not optical. And many thanks to Die, I'll take on board what you've said and act on it, meanwhile enjoy the oputside.
Can you borrow a 'simple' mouse from anyone/anywhere to eliminate the mouse?
In simple terms, a mouse with a rollball has two shafts, 90 degrees from each other. On the end of the shaft is a (simplistically) an encoder to tell that the shaft is revolving, and in which direction. From the two directions, the pointer knows where to go.
A couple of ideas.
Is your mouse in the sunlight? That creeping between the joints can affect the encoding (though it usually makes the mouse just 'freeze'.
Have a look in google with a search of "crazy mouse".
But, first, I would try another mouse to eliminate the current one.
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