### Godot version 3.4.3 stable ### System information Ubuntu 20.04.3 LTS ### Issue description When the `PitchShift` effect is added to any audio bus, it works well ONLY if the `pitch_scale` value does not change. If I change the value every frame dynamically, the audio will NOT play during the frames that the value has changed. See example project. I believe this bug was not present in earlier versions of Godot -- I have been working on a project through many versions, and haven't touched my audio code in many months. It used to slide through the various pitches. Now it cuts out. I have noticed it on my linux PC, as well as on an exported Android phone. ### Steps to reproduce See example project. The audio plays fine while the `pitch_scale` is an unchanging `1` If some code increment the `pitch_scale` each frame, the audio stops playing for all frames that the pitch scale is changed When it reaches `1.5` and stays there, the audio continues to play at the new pitch. ### Minimal reproduction project [AudioPitchBug.zip](https://github.com/godotengine/godot/files/8158614/AudioPitchBug.zip)