EW Version 7.4.0.8 Windows 10 Del M4800 Laptop

Has anyone else experienced this strange behaviour?  Asking here before raising a ticket on it. 

For a while now I and my fellow EW 'techie' - same build, different laptop have experienced an issue where if we want to change the order of items in a schedule we would click and drag the item using normal left mouse key drag behaviour. The selected item is picked up and the horizontal 'cursor' bar duly moves up or down indicating the place where the item would b e dropped into.   However, when we drop the item into the desired place it goes instead to another location, usually, but not always, to one item above where the location cursor bar points to. For example I have Schedule items 1 through 7. Lets say I want to drag Item 7 to be between items 2 and 3. I click on item 7 and drag so cursor bar is between items 2 an d 3. I release the mouse button and item drops into........between items 1 & 2 !

If I use the move up or move down in the Schedule context menu it works fine.  This behaviour also seems a bit random, sometimes it will work correctly, sometimes it will place the item several items away from the desired place. 

To try and troubleshoot I made and saved separate schedule files for each single item. I then created a new, blank schedule and dragged each single item schedule file back in  - A merge if you will.   The drag issue was then ok. But now, preparing a new schedule for Sunday upcoming, the problem is back again.  As I say, another user, same version, different machine is also seeing this strange behaviour.

Thoughts anyone?

Blessings 

I Have had this happen a few times before. Not very often. I haven't put any work into figuring it out. But it's never been aq constant thing for me. It's only done that to a handful of schedules to me throughout