To: groovy3130
Hello,
In AVS Video Converter it is not possible to adjust playback speed of the sound of the output file.
In AVS Video Editor, you can
change the speed of the video together with the audio. Or, you can
extract audio and
add it as a separate soundtack to your video. Then you will be able to adjust the speed of the soundtrack separately (right-click the soundtrack on the timeline and choose Speed).
Best regards