Audio Stutters

I'm working on a march right now. However, whenever I go to play it the audio stutters, sometimes doubling up on the notes. It makes it nearly impossible to actually hear how anything sounds. Any way to fix this? This happens with both Muse Sounds and Basic. Additionally, the app itself is overall just very slow. I feel like it's performance issues but I want to see if there's anything I can do to alleviate these issues without having to get a new computer entirely.