I am trying to play some native files (Preencoded) in lua script and calling the lua script in dialpan like below..

session:execute("playback", <path to file1>);
session:execute("playback", <path to file2>);
session:execute("playback", <path to file3>);

When I make call I hear file1 clearly but after that for approx 10-15 seconds I do not hear anything (except some occasional noise like breaking voice)

I tried commenting file1 (to check if file1 is corrupt or something) but then I hear file2 clearly and not file 3 for 10-15 seconds. I also tried session:sleep(100) between playbacks but issues remains same.

Am I doing something wrong?