So if the notes are spawning inside the box, that is because it's not performing well, since there's a desync between the map and the music itself. There's always going to be a little desync between them, which the game accounts for by shifting the spawn position of the notes, so the notes will still hit the target at the correct time. Unfortunately if there's too much desync between them, they'll be shifted inside the box, like you're seeing. If you just turned off that lag mitigation system entirely, the notes wouldn't be in time with the music, which would also make it unplayable. I'd like to go figure out how to prevent this, but that would be a lot of work, probably rewriting the whole map spawning system, so I'm focusing on Ch4 maps first