Windows 10: Excel does not scroll in continuous fashion with scrolling bar moving up or down

When I click on scroll bar at the right hand side of excel and drag it up or down, the spreadsheet used to also move up or down in continuous fashion. However, that is not working any more. Rather, what happens is when I scroll the bar let's say down and then I release the mouse, the spreadsheet moves discretely to that location. Any idea how to revert? I have no freezing panes. In fact, it was working fine even with frozen panes. Thank you.

:)

 

TPU review scroll bar

I was wondering if there was any specific reason the buttons to scroll down the list of reviews was stuck in the bottom left-hand corner? Whenever I want to read reviews, I always have to move my cursor and aim it at a small arrow that scrolls the reviews... I'd suggest that instead of making the arrows small and in a corner, it would be better placed to the sides of the review bar.

Something like this (yes, I know it's crappy but it took 5min to make):

 

Scroll bar on main menu scrolls straight to last item

When I click on the scroll bar of the main windows menu (bottom left button) and start to scroll down, the scrolling then continues automatically to the last item on the list so that I can't access the others. It is as if gravity has taken charge! There is no problem with scroll bars in web windows or in Excel. I think the same problem was happening in Word last week but it is not today. I have tried following various recommended fixes including a clean boot, running Windows defender scan and switching off some mouse functions. I am no computer expert so it is possible I have perforemd all these actions correctly. Nothing has solved the problem. I've also tried a different mouse.
Any suggestions as to what is the cause of the problem and how I might fix it would be very much appreciated. The graphics card is fairly ancient: could this be the problem?

 

scrolling bad

New event. When placing cursor over a list or row of columns, even the volume bar scrolling is automatic and proceeds to one end of the series and stops. The scrolling also stops when I move the cursor away from the list but am unable to select anything in the list. Not all the possible lists are effected. Other sites have recommended mouse/kb fixes. Have tried all those but the phenomena persists. Have not had any known updates recently and don't have a restore point to try. Any other suggestions? W10Pro 1903