Try all of the above. I had a problem mouse a while back which caused numerous things to happen which didn't seem mouse related, but were, including constant freezing and crashing. My very clever BIL told me what to do, which was most of the above. What worked was downloading new drivers for the mouse. (I cannot understand this as the computer is old, the mouse is old, there's no new software, I reloaded the original drivers, and still it needed new ones.)