Erratic Mouse

[DeeTee]

My PS/2 mechanical mouse suddenly developed a mind of it's own so I
purchased an optical mouse. One week later it is acting the same as the
mechanical mouse. Drag and drop more often drops rather than drags and other
times it will suddenly stick and then move around the screen without any
input from myself.

Has anyone any ideas please?

 

[DeeTee]

Thanks for your suggestion. I shall try rolling back the NVIDIA update.