menu -> debug -> experimental high speed handling
is it enabled?
anyway, i asked my server (rejetto.com) to download a big file from you (being admin on the forum i can see your IP), and from your-ip/~progress i saw about 140KB/s.
i know sometimes HFS is not fast enough.
i don't know at the moment how to improve speed in such cases.
i don't even have such a fast internet connection to make tests.