To avoid the issue of hosting large files on Github - the repo now links to remote downloads of the lectures (from dropbox).
Perhaps archive.org or Soundcloud if you're looking for a no-cost option.
EDIT : Here is sample dropbox download speed : http://cl.ly/Xs5J
> According to Dropbox support, public links for free accounts may not use more than 10GB of bandwidth per day while that limit is 250GB per day for paid Dropbox accounts.
OP responded to my post saying they were indeed disabled already. Dropbox is good for sharing with 1 or 2 people but bad for sharing with the general public.