You may need to turn to packet captures to get some clues then. I just did a quick capture while updating apps from my iPhone and see it is using different servers. Maybe try these:
CNAME su-cdn.itunes-apple.com.akadns.net., CNAME su-applak.itunes-apple.com.akadns.net., CNAME su.itunes.apple.com.edgekey.net., CNAME e673.a.akamaiedge.net
No guarantee they don't break other things or change, of course..
- Ex community all-star (⌐⊙_⊙)