it is possible to deactivate the php link protection manually but in my opinion , you shouldn't. I can get you a solution to bypass this protection for admin account but then the media will not work because the php link you are to input transfer to a webpage not direct link to a media file, doesn't it ?
I'd suggest you make use of the description box. You can insert sample in the Direct url box while applying bbcode tag to decorate the description. For instance, this goes to the description/lyric form
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