I enjoy decorating houses and in one I'm working on now I've done something rather special with the music, which I don't want any future visitors to miss out on. It would be nice to have a phrase such as "Turn your music on!" or simply "Listen" to let visitors know.
The game already has a similar message for when a player tries to use a playable instrument with their music off, and now that Ada Airedale sells castle magic spells to play specific tracks, it makes even more sense.
This is a good idea. Lots of players have their music turned off and the experience can be much better with it on. An idea I have to help you is to craft a treasure card display and to buy a castle magic card related to music scrolls, and put that on the treasure card display. Its not as good as a sign but that could hint a player to turning their music on