Cracking at end of audio?

I've recently made some of the audio in my 2D game be 3D and for some strange reason, there is a little crack / static sound at the end of each sound even though the audio clip is silent at the end and it isn't compressed. The volume of the static sound also seems to change each time as well.

Any help would be incredibly appreciated!

Edit: I've realised that it has something to do with the pitch but don't know why or how. When the player moves, to keep the footstep sound varied, I change the pitch each time the sound is played. For some reason this seems to cause the click sound but I want to get rid of it while still keeping the varied pitch if that's possible.