export multiple clips start-end problem

Ubuntu Studio 20.04, Audacity 2.4.2

I used Audacity to create separate clips of lecture. The export worked as far as creating a file for each label.
The problem is that each clip starts and ends late. I checked the audacity file to confirm that the audio between the markers begins and ends as expected.

Why are my selections time shifted?

Compared to what? In what manner?

Are you exporting as .WAV ?