Artifacts in unstretched (non apple) loops...

So... I have an audio file within a folder outside of the "Apple loops" folder and the single files folder. The audio file has data that is incorrectly embedded. turning off the follow tempo checkbox releases the audio file from the project's tempo and plays back at the original tempo and pitch, but it still has artifacts (as if it's still stretching or shortening). But it is at its original length and pitch. why am I hearing artifacts when it's not being stretched?