My site allows members to download large files, ranging from a few MB to in excess of 1GB in size. Currently, the site provides direct access to the file URLs and users authenticate via .htaccess when they click a link. I get acceptable 1MB/s download speed with the direct access method. I want to switch to using WP plugins. I have tried two so far, WordPress Download Monitor and Delightful Downloads, but both slowed the download speed to 20-30 kB/s -- more than 50X slowdown! Any suggestions?