Jan 20, 2017 - 10:28 AM
From your description, it sounds like everything is working as designed.
When you select a sound and a frame and then choose "Match Duration to Audio", you are performing an action on the selection.
However, the frame and the sound are not linked together (the sound is not contained in the frame) when the action is performed.
If you change the Audio start and stop points in the Options panel - you are not changing the length of the sound. You are changing what parts of the sound play.
It sounds like you have worked around the issue by changing the length of the frame. However, to get the level of precision you are asking for, you may want to edit the sound in another program like Audacity to shorten the sound. You can then add the sound back into Frames, select both frame and sound and then choose "Match Duration to Audio".