It’s just you probably. When you have the source or the program window selected you can input a timecode value and press enter to jump to that point in time. You can also use the plus or minus keys to add or subtract from the timecode.
We have no idea what you did with what settings so it’s kinda impossible to answer. “Looks great and fairly accurate” is not really a way to verify a calibration. I don’t know if DisplayCal has any verification features but I’d start with those.