C# - MP3 Download In An HTTP Response?

I've a question about something I'm searching for,for too long! We've build an application from which an admin upload songs into a database. Then user can bought songs and download it individualy. The problem is that when user download MP3 songs with the code below, it works great in Firefox and Chrome but not in IE8 simply because WMP trying to open the songs and it just don't get it instead of having a "Save as" dialog? Any issue on HOW can i force to have the "Save As" diaglog? Note that I have not MP3 physicaly on server it's in database. So I can't direct link to song ...

Here's my code :

// Remove "specials chars"
foreach (char aChar in @"/:*?""<>| ") {
if (aChar == ' ') {
songNameAndExt = songNameAndExt.Replace(' ', '_');
} else {
songNameAndExt = songNameAndExt.Replace(aChar.ToString(), string.Empty);
}
}
Response.Clear();
Response.ClearHeaders();
Response.ClearContent();
HttpContext.Current.Response.ContentType = "application/octet-stream";
HttpContext.Current.Response.Headers.Add("Content-Disposition", string.Format("filename={0}", songNameAndExt));
HttpContext.Current.Response.OutputStream.Write(songData, 0, songLength);