Old one but still relevant, I've got a customer running the beta who had this problem in 7.306 that is still showing up in 7.395
When going to Astaro Internet Security - Astaro Web Filtering Site Test and testing a URL it comes up as Media, but Media isn't in the firewall so they decided to try categorizing it as Internet Radio/TV and followed the link to SurfControl Submit-a-Site to find there is no Media or Internet Radio/TV to categorize the site as.
The site in question is Listen to music. Meet friends. - iJigg.com which is a streaming music site that he wants to categorize so his blacklist isn't 3 miles long, along with several other websites he has in the blacklist.