The problem is, that the user can zoom in on any part of the plot (see the attached image). Since I would like the labels to be for example 10:15, 10:30, 10:45 and not 10:23, 10:31, 10:39, this would mean that the labels are not equally spaced on the X axis, at the start point or end point.
In auto mode CVI does exactly the same, their first and last label are not the same width as the rest of the labels in between. But when you set the number of grid lines manually, the spacing is equal for every grid line, including the first and the last. As shown in the attached image, this is not an option.
Thus the question remains: is there a way to force the grid to only draw lines at places where the labels actually are defined? I've now just disabled the grid, but it would nice to have it back.