I used to be able to create my own custom ringtones from songs I like through iTunes and was able to change the format from .m4a to .m4r. I would then download them to the hard drive and copy them from the Music folder on the computer to the ringtone icon on the iPhone with the phone plugged in. Lately I've found the ringtones are still showing up on the phone but when when I connect my phone to a computer no ringtones show up and I can't add anything new either. Was there an iPhone update that made this impossible?