I don’t listen to music when I play IF Games. That said, if it’s a toggle option, I will listen to the music on a later playthrough.
I say go for adding music. Especially if it’s free. I think it’s a novel idea. Music has a way of bridging gaps that words can’t always nail.
However, one thing to keep in mind is that, for fast readers, sometimes the music won’t have finished playing by the time the scene ends! I’ve unintentionally cut off a lot of music tracks (so I try to pause for a moment to listen, which may or may not affect the scene’s tension/pacing). This is more a factor if you have more tracks to play or if you use the *sound nothing command.
Another thing to worry about: how long will the music last? You’ll have to decide if you want the music to play and stop, or loop to keep the overall mood of a scene. Looping would require you to manually repeat the track and upload that as one file. That way the music plays seamlessly across the scene—regardless of reading speed. Which can increase the overall file size of the game (only a factor for slower or older devices).
Lastly, you’d focus on consistency. When does the music play? I recall a IF where there was an unexpected scene music that startled players! It’s nice for the reader to know when music will be played. The WIP One Knight Stand also uses music and sound effects, but sometimes it can be unclear what sounds will take a priority or when sounds are supposed to play and when are some scenes silent. I think the WIP is a great starting point to see the reception of music/sound in an IF.
Anyways, it’s very nice if a reader can predict or have an intuition when music might play to create a smooth gameplay experience. If music is rarely inserted, it may be helpful to warn the reader about the upcoming sound. If music is frequent, it should feel invisible and seamless, which is the ultimate goal to adding music to our games.
I would advocate adding in a menu option in the stats menu to listen to the tracks at any point! Non-loop versions! I haven’t seen a game do that yet, and I would really appreciate it. 