I've tried putting a mp3 file onto the removable drive which is supposed to be the SD Card right? Then I disconnected the phone safely. I then went to Settings, Sound and Ringtones, then Phone Ringtone. It just brings up a list preinstalled ringtones. I know that its on the SD Card. It shows the title of the song everytime I plug the USB cable into my computer. Yet I can't seem to find it whenever I disconnect. What am I doing wrong?