Drumset Playback Issue

Whenever I playback the notes I have entered using either the 5 line or 3 line drumsets, there is a crackling/popping sound that occurs with a lot of the notes, almost as if those notes are clipping, though they occur regardless of the volume level. The crackling does not occur for notes that I have entered for other instruments (piano, violin, etc.). I have tried getting rid of the reverb on both the mixer and synthesizer menus, and the problem still occurs. I have tried playing the wav file of the song on my wife's computer and on my phone and the crackling still occurs. I am currently using version 1.3 of musescore, and my wife and I both have windows 8. Curiously, the crackling does not occur when I listen to the song as a midi file.

Thanks!