[Kiki Snell]

I know I’m super late to answering this question but I just figured out a simple and easy way to do this INSIDE of Adobe Premiere Pro.

1. cut the audio track just before the sound you want to extend
2. shorten the track so it ONLY plays that one note
3. right click and choose SPEED/DURATION
4. change speed to 10%-30%
5. under AUDIO TRANSITIONS in the EFFECTS menu, apply an EXPONENTIAL FADE to the end of the clip

DONE! 🙂