This is an excellent point and I see where you are coming from. However at the same time, you are not the marine, you aren't in the cold low-G alien ship ect... The eerie or triumphent music or whatever it was for any given level can really help you feel exactly what the marine is feeling. Music is like emotion made tangible. It is a style choice no doubt. But I miss the errie music for sure.
: I read Bungie's explanation of this a long while back. In typical Bungie
: fashion, they responded that they couldn't think of a reason why Leela (or
: Durandal?) was broadcasting the music of Alexander Seropian over the
: Marathon's loudspeakers throughout the invasion. It's a joke that sheds
: some light on their motivations behind the lack of music. It's all about
: destroying the barrier between the player of the game and character this
: player plays. In Marathon, you, the real live human being sitting at a
: computer get to bob (Bob?) your head and tap your feet to the tunes, but
: do you really think that the Marine heard that music all the way through?
: Of course not. The lack of music in Marathon 2 and Infinity broke down a
: barrier between player and character. If you heard it through your
: speakers, you know that He heard it through his ears. Marathon broke a lot
: of ground in this way, not just in sound design, but that's another thread
: and another day.