Just downloaded MainStage 3. None of the organs have sound below the note C2. Tried all other types of instruments and they all produce sound on all 88 keys. When attempting to play any of the organs, there is no audio, but the keyboard of my computer monitor shows the keys being activated…just no sound. I'm a complete novice. I'm trying to determine whether this is just me not understanding how the app works, or if there is something wrong. Any ideas? Thanks for the help.