Just in case this question is still relevant to someone thinking about buying the phone, I'll comment on it.
Volume is decent (although not super loud) and music sounds okay in general, but the signal to noise ratio is far from good, to be honest. There's a very noticeable hiss, probably due to internal noise generated by the electronic components of the phone. Using good quality headphones can help a bit but it's still prominent. It won't disappear with updates and it'll probably be even more noticeable with classical music.
If you're a bit of an audiophile, you're going to notice it for sure. I'm okay with it for casual listening (some music and podcasts while commuting; since there's quite a lot of external noise in those situations I don't notice the noise of the phone's audio that much) but I wouldn't use it as my main audio player (not at home, for example).
Edited by ahatomastarday, 03 September 2012 - 07:19 AM.