Jerky changes in view velocity when updating with timer

[Jeff]

Can you verify that the frame rate is stable throughout? Is the velocity fluctuating during that period of time when there is jitter? You could try recording the velocity values every frame and look at the values to see if it changes when you expect.

[rroemmich29]

When I log the velocities inside the update function, I get the following (as sample data):

500
467
220
54
612
497
398
418
700
585
776
825
346
297
552
388
817
542
811

You'll notice that none of the velocities become negative, so I am still struggling to understand why the jitter occurs. Certainly the velocity magnitude should change, but I'm not sure why it momentarily changes direction.