I thought I saw a comment from Jack about an option somewhere, but can't seem to find it. I know I can turn off all music, but I just want to turn off the title screen one. It's REALLY LOUD compared to all the other music in the game and hurts when playing on headphones. I don't remember having this issue with the beta song, but that one was much more muted.
The music controls in the preferences works globally: so if you lower/mute it, mutes the menu. There's no specific "mute only main menu one" But I should probably make it even less loud. Think that I even lowered the volume considerably vs the version the musician sent me!
This may seem silly, but when I was looking at it, I got annoyed by the loud music that would keep playing after I started the game, and nothing I did with the controls worked, turned out I had two windows of the game open with the title music blaring from one into my second.
Anyway I have lowered the track's volume, so on next update will be less loud. But I was waiting for a final "stable" release of Ren'Py before doing a new update (I made this game using a beta version, even if seems to work fine).