Audio File Processor - "pop" sound on repeat

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When I create a new instance of the strings.ogg sample and try to make it repeat, I get an ugly pop sound when the file repeats. I've tried editing the start/end points, and using some processing to minimize the noise. It's still there. Is this a sample rate issue?

Any thoughts?
There is a solution though, if you want to try it out ;)

In your instrument:

1. Go to the "ENV/LFO" tab (which is the second tab after "PLUGIN").
2. Below the graph that reads "Envelop", you can see some knobs ranges from DEL, ATT to SUST and REL.
3. To the right of the graph is "AMT". Turn it all the way to the right (Modulation amount: 1).
4. At the knobs below the graph, try turning "ATT" more than 0 (in this case, try 0.4).
5. If you still hear the pop sound, please continue reading, otherwise, it's fixed ;)
6. Now, try turning "REL" 0.05 or lesser and see if it works. If not, continue reading.
7. It is very hard to fix the instrument's pop sound at the moment. I have never heard a pop sound in my instrument for a very long time, and I'm pretty sure you can fix it using Calf Reverb, since that is what I used the most in my instruments.

Anyway, good luck with it ;)