Not sure what you're talking about, but there's no music/sound during the initial splash screen. There's also one standard question asking if you're 18+. After that you reach the main menu, that's where music starts. But at that point the options screen is readily available, where you can change the desired volume. The base volume is also automatically lowered to a 'relatively normal' level, compared to Ren'py's standard volume level.Urgh. Any game that will, on first start, make itself fullscreen, start blaring music at full volume, and not give access to a menu to immeditaley correct this until you have answered a bunch of stupid questions needs to be shot down. HavingAHardTIme is such a game.
To any game dev reading this: first impressions count. If my first impression triggers me to switch to a console to do a kill -9 and rm -rf to stop my eyes and ears bleeding, however much effort you put in your game doesn't matter.
Starting in full-screen is also normal for a game, especially seeing as most people end up playing full-screen anyways. Again, if you prefer otherwise that is fine, just change it in the options.
I'm sorry that this slight 2 second inconvenience caused you to bleed internally. Though, seeing as you had the time to write this comment, I doubt you value your time that highly.