The music ? There is no music... not sure what you mean by that.
It "crashes" when you win or lose, actually. The connection to the theme is that the game misleads you - it encourages you to strip mine the map as coldly and efficiently as possible but that only hastens your death - the "corruption" that comes in fact depends on how much Equirium there is left on the map. As such you can completely avoid it if you're patient ! Just gotta let the metal regenerate regularly, sort of lay the mines "fallow".
A simpler interpretation of the theme is the lie about the game's difficulty too. At first it's really easy, the natives don't attack you. All you (think you) have to do is just taking the map over and win. The corruption puts that notion under the ground.
Thanks a lot for your feedback, and for playing ! :)