Audio Watermarking?

[cercos]

Is there a way to add an audio watermark to an mp3 or any sound file with PHP? I Googled around and came up empty handed.

[litebearer]

Are you looking to add a short "disclaimer"/"Warning" mp3 to the beginning of your mp3's?

[cercos]

Kind of...more along the lines of adding a voiceover with my website name periodically throughout the mp3. In other words the user uploads their mp3 and it gets copied and the copy gets the water mark added to it.