I would like to request the option to play the audio on 0.5x speed on Acculips. When syncing it manually, this would be very helpfull, because 1x playback is too quick.

I don't know if this helps you, but once you've created your AccuLips clip, you can right-click on it in the timeline and select Set Speed.

In the popup dialog that appears you can the set the playback speed as a percentage.

This will affect the speech sound as well, so it's only useful for doing adjustments after which you should set the speed back to 100%.

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