I thought I'd post some of my observations on the sound issues.
Like everyone, it seems, only Leonard Nimmoy can reliably be heard on my computer (Macbook Pro 15", 2GHz, 2GB, 256MB VRAM).
However, using the options to use a custom music folder (my iTunes folder) I can more or less consistently hear music (fades out at the closest zoom and the globe view though). How odd!
Mind you, the custom music folder strikes me as a completely pointless option - except for debugging maybe. If I was going to do that I'll just use iTunes in the background as I always do because it allows me to, I don't know, use playlists, skip tracks... (But it was funny to see my computer's hard drive referred to as C: )