MDL notes not playing

So I made a cadence last night using the MDL software. Everything was fine but today when I listened to it to make some final touches, many of the snare notes (50% or more) just didn't play. I tried rewriting everything but to no avail. I also tried unplugging my headphones and using the speakers but the same notes were missing. What's weirder is that none of the other instruments are affected. The tenors, bass, and cymbals sound fine.