What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
21.12.24, I’m not sure if it’s 32-bit.
Can you repeat the problem? If so, what are the steps?
Yes. Reversing any clip at any quality causes the audio to crackle/pop.
It doesn’t matter if it’s inside the editor or exported.
Then you are reversing a clip, the audio is also reversed and will sound strange.
You can detach the audio from a clip before reversing it, to keep the audio unchanged.
(Right Click on clip and select More → Detach Audio)
The pops when reversed are possibly due to the video being variable frame rate and not seeking correctly during reversal. Convert the clip to edit-friendly first, then reverse the converted version.
When you choose the “Reverse” function, a dialog gives you an options for “good”, “better” or “best” quality. I noticed that “best” actually had the worst audio. The next release (22.01) will have an improvement so that all three quality options have about the same amount of “crackle/pop”.