32k & 64k bitrates are in question. 128k MP3 seems fine. I won't be able to reproduce the problem now since it's not peak anymore.
Here are my bandwidth results:
I have an 8 core system with 4G of RAM and plenty of power to spare. It's a co-located server with no known bandwidth restrictions on a gigE port. I don't have any intro files either. Maybe it has something to do with how many connections windows is allowing over the network? Results are the same with or without firewall.
Thanks for your help so far.