Despite the fact that we are capable of localizing dynamic sound sources, the mechanisms responsible for this are not completely understood since the majority of sound localization research has focused on static environments where the sound source and listener are both stationary. Although various auditory cues can provide motion information, intensity changes appear to be the dominant cue. Previous studies indicate that our perception of auditory motion is greatly overestimated when using auditory intensity cues solely. In this paper we describe an experiment that examines our perception of auditory-motion in the presence of a stationary sound source whose intensity decreases following one of five rates of acceleration. Preliminary results indicate that in order to detect a change in sound source intensity, this change must occur over a constant amount of time irrespective of the rate of acceleration in which the decreasing intensity is following.