EXTREME download times

Hi. I'm in the process of testing my zen cart before I go live. Everything has been working great so far, been able to overcome most difficulties I encounter. However, In the past 4 test runs, I have had extremely long download times for my product, downloading at about 16 kbs/sec. (Well over an hour, usually gets cut off part-way and "downloaded" file says corrupted) Here's the pertinent info. Any suggestions or help would be greatly appreciated! (Or is it just time to call my host/server?) (Have checked the forums, but can't seem to find an untried solution.)

zen cart v1.3.7 with March-21-2007 patch
php version 4.4.4
http server: apache/ 1.3.33
MySQL 4.0.27

-zipped file, 76.4MB, renamed file so it has no spaces or underscores
-download via streaming
-plenty of server storage/transfer space
-not marked as virtual product
-shared sever
-GZip compression disabled
-file is in download folder (permissions set to 755)

Only once has it worked w/in a "normal" download time (under 30 min).
Suggestions?

My first guess would be that this is a host related problem...

Is your host having a good connection to major backbones? What are the ping times? What about the server load(to full?!)?

Try this, just put a normal file for download and access it with a direct link. If it makes no difference with the zen-cart download, then it has nothing to do with zen, but with your host!

Will give it a try!!

I tried a 3MB file w/ a direct link and the download speed was still under 20kb/sec. That's unacceptable, so I will talk to my host and see what can be done. (Probably move to a dedicated server.) Thanks for the help!