I have the same issue. It occurred to me right after doing the most recent windows update around Valentine's day.
At first boot up in the morning, the wheel mouse scrolls very slowly. If I restart the computer, the scrolling works normally.
The next morning, same thing, the scrolling with the mouse wheel was extremely slow. For this instance, I unplugged the mouse (corded) from the back of my pc and reinserted it into the same usb port. This immediately fixed the problem; however, the next morning when I boot up for the first time, it's super slow again.
I unplugged the cord again from the usb port and tried another port (on the pc still - not a hub) and this immediately resolved the problem.
Today when I booted up, the scrolling is extremely slow again.
Note that in all instances of the issue, the settings on the pc were not changed or needed to be changed and even when changing them, they did not help the issue other than when drastically increasing the number of lines to scroll to get something that's close to what was normal scrolling for me. My mouse drivers are also all up to date.
Is there a fix for this?