Lowered the global volume to w180.
Point of advice: If you're using custom instruments, no need to repeatedly call the instrument command as they will play intended pitches just fine. It only applies to vanilla percussion instruments (@21~29). Otherwise, it just wastes space. I'm letting it through, as it's a minor issue for this one.
Also, I think it might be better to pan the first channel to the center and second channel panning to the opposite side of third channel for a more balanced panning.