1. I first tried to change the ring tone using dbus on the fly when receiving a call but it did not work. the phone just seems to go back to the default ring tone if you try to change it after the coming signal. 2. then I tried to just implement this solution but thought I could use no file extension for my symlink name first and then tried with mp3. It seems that the phone application either cache the file or resolves the symlink and store the absolute path when you first assign the ring tone to the profile. p.s. it does not seem to work on mine regardless of the file extension... the first time I set the profile ring tone to the symlink it works... if I change the symlink target the phone keeps playing the original file.... am I missing something?