advanced hotlinking block qustion

[eluser]Future Webs[/eluser]
Hi

Not specifically a CodeIgniter question here but I know we have talented people here that may be able to help.

The problem is this

I have a site that hosts mp3s and i already block people hot linking the files by using my htaccess file.

The other day whilst checking the site stats I noticed one file was being used far more then any other. After a bit of digging I found that the file was being hot linked from another domain but the htaccess file was not able to block it.

The reason it cant block it is because the mp3 file is being called from within a flash mp3 player hosted on the other site.

So the question is this.

How do I block files on my site from being called from within a flash file on an outside site ?