- You may need to update your Winamp software. Go to http://www.winamp.com/ and download the new version.
- You may have your filetypes mismatched or not mapped at all.
- Open up Winamp
- Press CTRL+P to open up preferences.
- Select Setup->File Types in the left pane.
- In the "Associated extensions" box, make sure that pls is highlighted
- Open up Winamp
If this still failes to still work then contact a support staff member.