Hey man,
When in through till end trigger mode it is correct behaviour for the sample to play from the cue through until the end of the audio file. To avoid this behaviour you will need to set an out point for the cue. You can find this information in this article under the heading "cue position and length":
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If after reading and applying the steps from the article you're still having issues please open a help request with our support team (click on the green open help request button at the bottom of this page).