MBT Display Timing Discrepancy

I am still testing X1 1b trial.   Found another problem tonight, probably another graphic bug.

In track view, play a short monophonic melody on a simple instrument, like piano.  Tempo 120.

Observe the MBT display in track view, it should run smoothly and accurately, and it does exactly that.
Now switch to staff view, and the exact same MBT display becomes sluggish, inaccurate and clumsy looking. 

Jerry