Timestamp controls don't work exactly right

[ThomasHaine]

The numbers on the timestamp controls don't adjust the slider or the printed datetimes.

When I move the slider controls, both the numbers on the right, and the printed datetimes adjust accordingly. This is what I expect.

But when I adjust the range with the numbers (e.g., by typing a new number, or using the up/down arrows), the sliders and the printed datetimes aren't updated. They should be.