from the FL 5 reference manual
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6. Sample View
The sample view displays the loaded sample (with all precomputed effects applied). It also shows the loop points and region locations, if such exist (loop points and regions can be set by using an external wave editor). The first vertical red line is the loop start point; the second one is the loop end point. Left-clicking the sample view previews the sample (if time stretching is enabled, the preview is tempo synchronized). Right-clicking it shows a menu with additional channel settings and commands. It contains exactly the same entries as the menu you can call by clicking the button at the top left corner of the Channel Settings window.
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That means if you recorded it and it doesn't hit exactly at
the beginning of your transient, you have to edit out the stuff
before using a wave editor like soundforge, wavelab, cool edit,
audacity (free), etc.

Peace.