So I found this in the documentation...
To ensure files are protected from direct linking, Force Download can be used. Files will be served by PHP. However, if your files are large, or server is underpowered, you may experience timeouts during download – in this case you would need to either look at your server or use the redirect method.
If your server supports it, use X-Sendfile; its the most reliable method. Apache serves the download giving you the best performance. Files are also protected by a .htaccess file making this method secure.
So it appears to be the server setup. However, it is somewhat vague and doesn't specifically state what to look for on the server. There is the mention of X-sendfile for security, which I definitely want to use. However, I don't think GoDaddy shared hosting allows for this method. Which means I would probably have to upgrade the plan to a Virtual Dedicated or find hosting elsewhere. That's a huge step to take though without knowing whether or not it is going to solve the issue. Anyone have any experience with this issue?
Thanks,
Wil