DelayAudio

AviSynth+
Up-to-date documentation: https://avisynthplus.readthedocs.io

DelayAudio(clip, float seconds)

DelayAudio delays the audio track by seconds seconds. seconds can be negative and/or have a fractional part.

Example:

# plays audio half a second earlier
DelayAudio(-0.5)

PS: if audio loaded from separate file (for example WavSource), it's better do negative delay after AudioDub this clip, or else it may cause problems.