Fixing Unwanted Slow Audio Fade-Ins

Do you suffer from an unwanted slow audio fade-ins whenever starting playback in the timeline or in the clip monitor, while you do not have any audio fade effects applied at all? Turns out this is some odd interference between some(!) USB audio cards and the PulseAudio sound backend.

ALSA to the Res-Cue

Luckily, there is an easy remedy in case you are affected.

Go to Menu ‣ Settings > Configure Kdenlive, then in the configuration dialog select the Playback section. Change the Audio driver from Automatic to ALSA. Leave the Audio device set to “Default”, so your desktop audio device settings apply.

Click OK, and you are done.

Your timeline and bin clip audio playback should now be working as expected, without any unwanted slow audio fade-ins anymore.

You will find the corresponding option in the main menu via Menu ‣ Sequence ‣ Disable Timeline Effects. This disables or re-enables all timeline effects, that is, timeline clip effects and track effects.

However, please note that prior to Kdenlive 16.08.1, track effects are not properly disabled or re-enabled by Menu ‣ Sequence ‣ Disable Timeline Effects.

Please see Effects Everywhere about how to temporarily disable bin clip effects.

Notes

Background Information

Please note that the unwanted ~2 seconds audio fade-in only happens with some USB audio cards but not others. It was noticed when trying a Steinberg UR22mkII USB audio interface.

Using the UR22mkII in Kdenlive using the stock audio settings was impossible, as the automatic fade-in made any voice over editing a complete and utter fail. Curiously, the UR22mkII worked beautifully when playing back audio using an Android tablet (that is a beautiful aspect of the UR22mkII: it is designed to be used with mobile devices). For comparison, a (much bulkier) Behringer QX1202USB does not exhibit the strange behavior even with the default audio settings in Kdenlive, or when using PulseAudio.

And what is even more strange and surprising: at least some other software, such as VLC, are completely unaffected, even when using PulseAudio for audio output.

Sources

The original text was submitted by user TheDiveO to the now defunct kdenlive.org blog. For this documentation it has been lifted from kdenlive.org, updated and adapted to match the overall style. *[RGB]: Red Green Blue *[VFX]: Visual Effects *[feathering]: Smoothing or blurring the edges of a feature *[LFO]: Low-Frequency Oscillation *[dB]: decibel *[LUFS]: Loudness Units Full Scale *[AI]: Artificial Intelligence *[LLM]: Large Language Model *[HSV]: Hue, Saturation, Value *[SOP/Sat]: S(lope), O(ffset), P(ower) / SATuration *[CDL]: Color Decision List *[HSL]: Hue, Saturation, Lightness - Using HSL color space is useful for subtle color changes *[px]: pixel *[hh:mm:ss:ff]: hours:minutes:seconds:frames *[Hz]: Hertz *[CIE]: Commission internationale de l'éclairage, French for International Commission on Illumination *[DCI]: Digital Cinema Initiative *[nadir]: direction pointing directly below a particular location *[OS]: Operating System *[decibel]: Unit of measurement (dB) for sound levels *[clipping]: A form of distortion that limits a signal once it exceeds a threshold *[Spectrogram]: Visual representation of the spectrum of frequencies of a signal as it varies with time *[prevent clipping]: Dynamic range compression (DRC)is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, thus reducing or compressing an audio signal's dynamic range. *[SNR]: Signal-to-Noise Ratio *[dbFS]: Decibels relative to full scale *[QHD]: Quad-HD *[UHD]: Ultra High Definition *[XML]: Extensible Markup Language *[fps]: frames per second *[NTSC]: National Television Standard Committee - defined the TV system used in the United States, Japan and many other countries *[PAL]: Phase Alternating Line - a colour encoding system for analogue television *[LFE]: Low Frequency Effects *[RAW]: The RAW file format is digital photography's equivalent of a negative in film photography: it contains untouched, raw pixel information straight from the digital camera's sensor *[DSLR]: Digital Single Lens Reflex *[DOF]: Depth of Field *[NDF]: Neutral Density Filter *[AVI]: Audio Video Interleave *[BT.601]: A standard from 1982 defining how RGB color primaries get turned into the YCbCr channels used by modern codecs *[BT.709]: A standard from 1990 which does the same at BT.601 but the transfer coefficients are slightly different *[grep]: A Unix command-line utility for searching plain-text data sets for lines that match a regular expression