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Audio recording has "clicks" half the time
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Description

See original message here: https://lingualibre.org/wiki/LinguaLibre:Chat_room#Audio_recording_has_.22clicks.22_half_the_time

A copy below:

I've had friends record German and Romanian lists. They're using separate hardware, and have recorded thousands of words before, so I know their hardware is fine. The recordings they've done today suffer from loud clicks on half the recordings, so there seems to be a problem with the recording studio. I clearly have no idea what the problem is or how to fix it, but I hope someone else will!

Here are examples:

https://commons.wikimedia.org/wiki/File:LL-Q7913_(ron)-Andreea_Teodoraa-musc%C4%83.wav

https://commons.wikimedia.org/wiki/File:LL-Q188_(deu)-Natschoba-der_Wunsch.wav

This problem is confirmed by another contributor.

Event Timeline

Pamputt triaged this task as Unbreak Now! priority.Sun, Apr 25, 6:13 PM

I think some samples are missing. I looked at LL-Q150_(fra)-Hélène_(Hsarrazin)-corné.wav in Audacity. There's a discontinuity at 0.3405s which could be explained by about 1ms of missing samples:

The discontinuity is easily visible in the spectrogram view. Once you zoom in, you can find it in the waveform view.

Similarly, here's one of at least two pops in LL-Q188 (deu)-Natschoba-der Wunsch.wav. The amplitude is modest, but again, the spectrogram (and the ear) easily picks it up.

It looks a bit like a duplicate of T197599, although I can confirm that the commit which is supposed to have fixed that issue is live on lingualibre.org. And my understanding of T197599 is that it can only cause one pop per recording, whereas e.g. LL-Q7913 (ron)-Andreea Teodoraa-ofițer.wav seems to have four.