Provided by: allegro5-doc_5.0.10-2_all 

NAME
al_set_sample_instance_speed - Allegro 5 API
SYNOPSIS
#include <allegro5/allegro_audio.h>
bool al_set_sample_instance_speed(ALLEGRO_SAMPLE_INSTANCE *spl, float val)
DESCRIPTION
Set the relative playback speed. 1.0 is normal speed.
Return true on success, false on failure. Will fail if the sample instance is attached directly to a
voice.
SEE ALSO
al_get_sample_instance_speed(3alleg5)
Allegro reference manual al_set_sample_instance_speed(3alleg5)()