QA40x THD vs Frequency automated test power level increments

Often, but not always, I am not able to have the last input signal level range hit. For instance, with these settings:

The desired stop level was 0.9dBV, with 3dB increments from -11.1dBV. After running the test, the last input level that was applied was -2.1dBV, 3dB away from where I wanted to be. I would say that I am not able to hit the last level often, but every now and then I do. I thought I have seen a post on this somewhere, but it would be nice to know how to do this more successfully. Thanks for any suggestions!
Here is an update: I wanted to go to -3.1dBV for the last step, and when I set the stop level to -3.1dBV, it only went to -6.1dBV. I then changed the stop level to what you see below, -2.7dBV,

and hit the desired -3.1dBV… Thoughts???

Hi @Var, that is correct. The steps will generate evenly spaced points as you specify. So, if you specify 2dB steps from -10 to -5, it will be -10, -8, -6, and there won’t be a -5 generated. There are pluses and minuses will trying to guess the operator intent, I guess. The frequency steps in some plugins do fill in the last step you specify even if it’s missed due to step size. At a minimum, I do think the behavior should be unified for freq and amplitude in the code. Probably it makes sense for user-specified start and stop to be included even if that means a redundant point is sometimes generated.

I noticed that happening for the frequency increments but just started going a bit wider, maybe go from 10hz-22khz and set the x-axis min to 20hz and 20khz max and everything works out as I usually don’t care about the thd at 10Hz for most things I measure. I will try setting the max pwr limit to 0.4dB lower than I want to go the next time I run that test and see if that seems to work. Thanks for the feedback.