Files stop playing in the middle of the file

If you set the "Prevent local caching" option when using the Customizer tool, try using the Customizer tool again and turning this option off.

Using the "Prevent local caching" option causes the MP3 files to run through PHP (ASP) rather than the file going directly through to the browser. Depending on how your server's PHP installation is set up, if a very large files is moved through PHP, PHP may "time out" and therefore only a portion of the file is transferred to Wimpy, which would result in the file not being fully loaded or fully played.