Bug 514662

SUMMARY
When using Kdenlive's "audio capture" to capture voiceover directly from my interface, the audio is stuttering and appears to be dropping significant amounts of the information. It almost seems like a sample rate mismatch but the file generated *is* the correct sample rate. I did not notice this issue in 25.08 so I think it's new in 25.12. I first observed it in 25.12.0 but today I downloaded 25.12.1 and it was still there.

I originally thought it might have been related to issue #493308 but on closer inspection it looks like a new bug. I've confirmed with a few other Kdenlive users that they too are running into this issue.

My particular interface is a Focusrite 2i2, and I'm running Debian Trixie (I've observed this issue on GNOME and KDE Plasma).

STEPS TO REPRODUCE
1. Arm a track for recording in the audio mixer
2. Record a sample of audio from the timeline

OBSERVED RESULT
When playing back the audio, it doesn't look like the waveform that was recorded (it's shorter and missing large chunks of data). The audio is stuttery and disjointed, as though the sample rate is incorrect (even though it matches what we see in the settings dialog).

EXPECTED RESULT
That the captured audio looks like the waveform that was recorded (takes the same amount of time and isn't dropping large chunks of data). That the audio sounds like what was recorded.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian Trixie w/GNOME 48 (although I also observed this on KDE Plasma)

ADDITIONAL INFORMATION
I put together a short YouTube video walking through what I'm seeing, because it's quite hard to articulate the audio stuttering without hearing it for yourself. https://www.youtube.com/watch?v=T7LBGSi2WSs

Thank you!