I've attached a video of the behavior.
I've created some state-pattern code to run my device. So far I'm pretty happy with it until I created a "Menu" state. I've created some high level functions to shift/animate text around in my menu state. When within the menu state the device seems to run MUCH slower than when it's in another state. This is shown by how slow the text slides when in the Menu mode. When out of the menu mode, you can see how fast the text is supposed to move. WHY?
Video Clip:
(Yes, I know I have a few typos in the menu item counter )
Some thoughts, the scrolling text in the "Menu" is within the interrupt handler while the other code where there is scrolling text is not within the interrupt handler. Could that have any effect? I also might have some locking going on, but I'm not sure how to really diagnose it.