erratic keyboard autorepeat behavior on particular program

I'm using old application named Jot Notes, developed for Windows in the 90s King Stairs Software.
It has worked flawlessly on all Windows versions through Windows 7.
On my specific Windows 8 laptop (Dell 3147) there is a serious issue.
When scrolling through a text note that is long, the keyboard repeat rate gets progressively slower as I advance through the note, so at the bottom
of the note, the repeat rate is very slow, for example when I hold down an arrow key to advance the note line by line the repeat rate is over 1-second.
A few key points. This issue doesn't happen in notepad, wordpad or MSword. Also, I tried an external USB keyboard and the problem still occurs. Interestingly, I tried a friend's Windows 8 laptop and this issue was absent (Jot Notes worked completely fine on my friend's Windows 8 lapop). I wonder if there is some Windows 8 setting that could be causing my issue. This is extremely annoying and I want to see if there is a way to troubleshoot and fix this issue. I would appreciate some guidance.
Thanks