Bug 488038

SUMMARY

A while ago I had taken some audio from my friends and used Kdenlive to turn them backwards, as a joke.

But yesterday, when I tried to revert them again and get them back to normal, it didn't work and Kdenlive only rendered noises.

The strangest thing is that when I try to reverse these audios using another program, the audio is reversed correctly and I get the original audio. I tested using the website https://audioalter.com/reverse

STEPS TO REPRODUCE
1. Place any audio on the Kdenlive timeline

2. Under “change speed” check the “Reverse clip” box.

3. Render the audio as mp3. Works as expected. Let's call this file reverted.mp3

4. Insert the reversed.mp3 file into kdenlive and try reversing it a second time to get the original audio back.

5. Now the audio has become just noise. It's not just in preview, but when rerendering as mp3 (like double-reverted.mp3) it still doesn't work.

6. The strangest thing is that there is nothing wrong with the first reversal. If you take the reversed.mp3 file and try to reverse it again using another program like https://audioalter.com/reverse it returns to the original audio correctly.

I made an example video showing the problem, edited entirely in Kdenlive:
https://www.youtube.com/watch?v=qc9x6Yr62VY

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch Linux
(available in About System)
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.2.0
Qt Version: 6.7.1

ADDITIONAL INFORMATION
ffmpeg version: 6.1.1