Strange Scroll Behavior in Terminal

Using the latest version of WebStorm on Windows 10.  When scrolling in the terminal window I am getting some odd (but not so random) characters appearing.

Example:  C:\code\project>Mav(MaU'MaU'MaU'M`]&M`]^\M]

This only happens in the terminal window within Webstorm - no other windows, no other apps.

I typically use the trackpad, but it also occurs using my mouse - if I scroll kind of fast.

This has not always been an issue, but I really cannot say when I realized it was doing it.  Rough guess - sometime in the last month or so.  I can't say what all may have changed in that time - OS updates, Webstorm updates, etc.

Some details:

1. Windows 10 (latest updates - not insider)
2. Webstorm 2016.1.1 (145-597 built Mar 30)
3. Dell XPS15 (9550)
4. Logitech MX Anywhere 2 mouse.

Any ideas?  Time for a ticket?  It has rendered the terminal window fairly useless at this tiime