As a sideinfo, in the Mixer Menu there are individual mutes for the drum instruments as well (the two button rows 1-16).
Thank you Zaq! This was the issue! I went into mixer mode and held down my track and found that 3 of my instruments (including the troublesome snare) were lit up, signifying that they were muted.
Zaq, this firmware is such a cool thing. Thank you very much for developing it!