Problem with mouse settngs

Hello, I was able to fix my erratic PS/2 mouse
(occasional clicks not recognized, jerky movement)
by going into the device manager advanced properties
and turning off "fast initialization" and adjusting
"sample rate" to 80 - it works great.

Here's the problem. After a few days, I notice the
problem with the mouse again, go into device manager,
and sure enough, the settings have reverted back to the
defaults.

Anybody have any idea's why this is happening ?